AIDS TO TECHNICAL WRITING ·RICHARD C. JORDAN, Ph.D. ASSOCIATE PROFESSOR AND ASSISTANT DIRECTOR ENGINEERING EXPERIMENT STATION

MARION J. EDWARDS, B.A. RESEARCH ASSISTANT

•

BULLETIN NO. 21

UNIVERSITY OF MINNESOTA ENGINEERING EXPE·R IM~NT STATION MINNEAPOLIS VOL. XLVII

NO. 24

MAY 15, 1944

Entered at the post office in Minneapolis as second-class matter, Minneapolis, Minnesota. Accepted for mailing at special rate of postage provided for in section 1103, Act of October 3, 1917, authorized July· 12, 1918.

COPYRIGHT,

1944

BY THE UNIVERSITY OF MINNESOTA

Setting up a guide for technical writers, as this bulletin attempts to do, has necessitated the co-operation of many organizations and individuals. Among those who assisted freely in the preparation of the publication were Dr. Anna A. Phelan, assistant professor, Department of English, University of Minnesota, and the University of Minnesota Printing Department. Their interest and suggestions, coupled with the co-operation and encouragement of Professor Frank B. Rowley, director of the Engineering Experiment Station, were extr~mely gratifying to the authors. Many other organizations were helpful in the compilation of material, and specific reference is made to these throughout the bulletin.

iii

CONTENTS CHAPTER

'I

PAGE

1 1

PLANNING FOR THE PRINTER..................................................................................................................... Page Appearance ................................................................................................................................. Divisions of Publication ...............................................................................................................

2

II

STYLE IN NoN-LETTERPRESS PUBLICATIONS........................................................................... Special Typewriters ........................................................................................... _............................ Outline of Contents ........................................................................:..................................................

6 6 7

III

PREPARATION OF MANUSCRIPTS FOR MAGAZINES..................................................................

16

IV BIBLIOGRAPHY FoRMs .................................................................................................................................... Special Cases .......................................................................................................................................... Form in Non-Letterpress Publications........................................................................

18 18

22

v

FOOTNOTES ······························································································································································· Kinds of Footnotes ........................................................................................................................... Forms ............................................................................................................................................................... Setting up Footnotes in Manuscript.............................................................................. Footnotes in Non-Letterpress Publications............................................................

23 23 23 28 28

VI

NUMBERS ····································································································································································· Words or Figures .............................................................................................................................. Numbers in Outlines ..................................................................................................................... Arabic and Roman Numerals ................................................................................................ Numbers in References ............................................................................................................... Special Rules ..........................................................................................................................................

29 29 29 30 30 30

VII

EQUATIONS ...............................................................................................................................................................

31

VIII

TABLES ........................................................................................................................................................................... Organization ..............................................................................................................,............................... Table Headings .................................................................................................................................... Ruling ............................................................................................................................................................... Reading Matter .................................................................................................................................... Footnotes ...................................................................................................................................................... Alignment ................................................................................................................................................... Omissions ................................... :............................................................. :....................................................

32 32 32 33

IX

PROOFREADER'S MARKS ..............................................................................:.................................................. Inserting Cuts .......................................................................................................................................... Two Kinds of Corrections............................................................................................................

37 37 37

X

PHOTOGRAPHY IN TECHNICAL PUBLICATIONS...........................................................................

40

XI

ABBREVIATIONS FOR SCIENTIFIC AND ENGINEERING .TERMS.......................................

50

XII

CONVERSION FACTORS ....................................................................................................................................

54

XIII

LETTER SYMBOLS ................................................................................................................................................ Letter Symbols for Hydraulics ......................................................... ,............................. Letter Symbols for Mechanics of Solid Bodies ............................................. Letter Symbols for Heat and Thermodynamics Including Heat ·Flow .........................................................................................................................................................

63 64 67

iv

33 34 35 35

69

PAGB

CHAPTER

XIV PREPARATION OF DRAWINGS FOR PUBLICATION.................................................................. .'..

.

XV GRAPHICAL SYMBOLS ............................................................................................:................................ :...... 85 ' XVI

PREPARATION OF CHARTS AND TABLES FOR LANTERN SLIDES ................................. 106 ·

i:~fe~~;n ....·.·:.·.·.·.·.·.·.·.·:.·.·~·.·.·.·:.·.·.·.·.·.·.·.·: .·.·.·.·.·:.·.'.'.'.'.'.'.·.·: .·:.·.·:.·.·.·:.·.·:.·: .·.·: : .·:.·.·.·.·:.·:.·: :.·: : .·.·:.'.'.'.'.·.·:.·.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.'.':.": : : : : :.":.'.'.'.' i~:. Line Weights ............................................................................................................................................. 110 Curves and Charts .............................................................................................................................. 110 Tables .............................................................................................................................................................. . BIBLIOGRAPHY

ILLUSTRATIONS FIGURE

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37.

Balanced Arrangement of Cuts on Facing Pages .......................................................... .. Narrow Cut Leaves Space for Printing down the Side ............................................. Outer Margins of Cut in Alignment with Print .............................................................. . Standard Form for 81fz"x11" Title Page .................................................... :................................ .. Variation of Standard Form for 8%"xll" Title Page................................................. .. Standard Form for 6'~x9" Title Page .............................................................................................. . Variation of Standard Form for 6"x9" Title Page ......................................................... · Halftone Reproduction from Flat Print. .................................................................................... .. Halftone Reproduction from Glossy Print .............................................................................. Dots not Easily Seen in Ordinary Halftone Reproduction ................................... . Macrophoto Shows How Screening Converts Picture into Dots .................... ." Original Photograph Was 8"x10". Detail Is Good in One-half Linear Reduction ........................................................................................................................................................... . Two-thirds Reduction from Original .............................................................. ~ ............................ . Three-fourths Reduction from Original .................................................................................... :. Dark Background Does Not Show up· Apparatus ............................................................ Light Paper behind· Apparatus Emphasizes Outline and Detail.. ................ .. Useless Shot Attempting to Picture Engine in Foreground............................... .. Angle of Shot Changed .................................................................................................................................. .. Artificial Background Used ................................................................................................................... .. General View of Equipment. .................................................................................... ,............................. .. View of· Equipment Gauges ....................................................................................................................... . View of Dust Feeding Apparatus of Equipment... ......................................................... Untouched Photograph of Apparatus ........................................................................................... .. Photograph Retouched ................................................................................................................................ . Reproduction from ·Original Print. ................................................................................................... .. Reproduction from Halftone ................................................................................................................ .. Guide for Lettering Reduction. Full-scale Re~prodlUC1tioln .................................... ~ One-fourth Reduction of Original Lettering ...................................................................... .. One-third Reduction of Original Lettering .................'........................................................ .. One-half Reduction of Original Lettering ............................................................................ .. Two-thirds Reduction of Original Lettering ........................................................................ Three-fourths Reduction ......................................................................................................................... .. Guide for Line Reduction. Full-scale Reproduction ..................................................... . One-fourth Reduction .................................................................................................................................. .. One-third Reduction ..................................................................................................................................... .. One-half Reduction ......................................................................................................................................... . Two-thirds Reduction ................................................................................................................................ .. v

PAGE

FIGURE

::.8. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 50. 51. 52. 53. 54. · 55. 56. 57. 58. 59. 60.

Three-fourths Reduction ........................................................................................................................ . Symbols for Section Lining and Outside Views ........................................................... .. Symbols for Plumbing ................................................................................................................................ . Symbols for Plumbing ·························'······································································································· Symbols for Plumbing .................................................................................................................... :........... . Plumbing, Sprinkler, and Pneumatic Piping Symbols .......................................... . Symbols for Pipe Fittings and Valves .................................................. . Symbols for Pipe Fittings and Valves......................................... ..................... . Symbols for Pipe Fittings and Valves .................................................................................... . Symbols for Pipe Fittings and Valves ................................................................ . Symbols for Heating and Ventilating ........................ . Heating and Air Conditioning Piping Symbols Symbols for Ductwork ............................ . Symbols for Ductwork ...........................,........... .. Symbols for Heat-Power Apparatus ...... . Symbols for Refrigerating ........................ ................................................. . Symbols for Refrigerating ....................................... . Symbols for Conventional Rivets .................... . Symbols for Welding ...................................................... . Symbols for Welding · ............................................................. . Chart Properly Prepared for Standard Slide Lantern Slide Too Detailed for Quick Analysis Same Slide Simplified for Projection .........

83

87 88

89 90 91 92 9.3 94 95 96 97

98 99

100 101 10'2 103 104 105 107

108 109

TABLE.S NUMBER

I II III IV V VI VII VIII IX X XI XII XIII

Bibliography Forms ........................................... . ......................................................... 19-20 Footnote Forms .......................................................... . ......................................... 24-25 Common Footnote Vocabulary ................ ..................... 27 Long Headings May Be Set at Right Angles.... .. .....................,............. 32 Center Reading Matter in Column or Align It with Left Margin........ 33 Center Reading Matter in Table ......................................................................... 34 Place Footnotes Immediately below Table........................ ...................... 34 Center on Decimal Point if Units of Measure Are the Same... 35 Align According to Margin if Different Units Are Listed.............................. 35 ·Include Ciphers if Omission Is Confusing. ...................... 36 Omit Ciphers if Value Is Clear............ ......... .......... 36 Line Width and Letter Height for Commercial Templates and Pens 75 Minimum Letter Heights for Satisfactory Legibility on Drawings Prepared for Reproduction ........................................................................... .. 81

vi

The effectiveness of a technical publication, apart from actual information, is influenced by three important factors: (1) style of presentation, (2) general format, and (3) illustrations. Style of presentation depends primarily on the author's training and practice in the use of the English language and his experience in writing for publication. As such, it is beyond the scope of this bulletin. However, the proper design of the format, the preparation of illustrations and drawings, the use of accepted symbols and abbreviations, and the correct handling of bibliographies, numbers, and equations should not be left to the chance experience of the author. These phases of technical writing accomplish their· purpose best when they follow approved methods. This bulletin aims to segregate and summarize methods which lead to interesting and effective technical writing. Approximately thirty years ago the initial efforts were made toward standard.ization in the preparation of charts, graphs, and diagrams. These efforts resulted in the formation of the American Standards Association, which has ·greatly assisted authors in the proper presentation of technical data. The work of the association is frequently quoted throughout this pamphlet. Aids available to writing in all technical fields are too numerous for inclusion in this booklet. Hence, all aids for one field-that of mechanical engineering-have been completely presented. The mechanical engineering aids are representative of assistance available for other fields. For example, graphical symbols are i:(lcluded for mechanical engineering, and references only are included for similar graphical symbols for electrical, aeronautical, and civil engineering. Most of the material, however, is applicable to all engineering fields, and only where information in all fields is too bulky has it been limited to mechanical engineering. The proper preparation and presentation of charts, graphs, and illustrations, as well as slides, have been em-,. phasized~ The value of illustrated technical matter is shown by the discovery of the United States Navy that its trainees absorb printed material best when it is elaborately illus ... trated. Good graphs and illustrations enhance the appearance vii

of a publication and make its contents more interesting. Poor graphs and illustrations may greatly harm a publication. Ineffective drawings and slides in many cases may be t:caced to improper lettering size and line weight in the original drawings. For this reason,--reduction scales for lettering and for line weights, as well as suggestions for correct handling of illustrations, are included. This bulletin is directed to those interested primarily in engineering rather than in writing. It is based upon the premise that a technical publication should be clear, concise, and well illustrated, and attempts to present means to that end. -

viii

CHAPTER I

Planning for the Printer ·

E

VERY technical author should be aware of the possibilities and limitations of a· printed page. Otherwise he may demand the possible of the printer. This chapter offers suggestions concerning· , page arrangement, general style, outline patterns, and standard divi-. · sions. The suggestions are based on forms now in use and on forms advocated by authoritative style guides.

im-

PAGE APPEARANCE

In the printer's terminology, the left-hand page is called the "versq" and .the right-hand page, the "recto.)' The layout of the two pages aims to prese:q.t a single, well-balanced picture. Illustrations will be most effective if placed according to a certain scheme in the picture. Placement of cu:l:s

The author must not assume that the printer will know the purpose or value of his illustrations. Figures and illustrations may appear in a size or position tending to distort their meaning. In the chapter· of this bulletin entitled "Effect of Reduction .on Lettering and Line Width" the process and effect of reduction is explained and illustrated .. Using this chapter as a guide, the author should be able to avoid hav... ing his illustrations reduced below the minimum for clarity. Informa- · tion on reduction of photographs is given in Chapter X, pages 40-42. · Once reduced to a desirable size, the illustration must then be inserted in the most effective position. If two cuts are to be placed on each side of a page, the best arrangement is in the upper left and lower right corners on the verso, and in the lower left and upper right· corners on the recto (see Figure 1). If a single cut is to be placed on a page, it should either be ~mall. enough so that its border lines up with the outside printed margin with printing indented down the other side (see Figure 2) or else the cut should be large enough so that it is in fair alignment with both printed margins (see Figure 3). S:tyles of :type

In making requests of the printer, the rules of good taste in printing should be kept in mind. Harmonious styles of type should be combined throughout the publication. Shades of type may be varied from light and medium to bold, and heights (measured in points) are chosen· to follow a regular pattern for copy and headings. Discuss your pub~ lication with the printer if you wish to have a part in the selection

AIDS TO TECHNICAL WRITING

2

Figure 1. Balanced arrangement of cuts on facing pages (Published with permission from 1942 Refrigeration Data Book, pp. 492, 493.)

of type. Quite often, even where regulations demand adherence to one style, variety may be introduced by changing some headings from light to bold face. DIVISIONS OF

PUB~ICA TION

The main divisions· of any publication, technical or otherwise, are three: preliminaries, text, and reference matter. In books each of these divisions is extended and enlarged beyond the length required by briefer publications. The regulations under which technical bulletins are often published may require a certain plan for each of these parts to follow. Usually there is ample leeway, and it is well to know the customary patterns in use so that cumbersome or awkward makeup does not result. · The preliminaries

Most of the following parts will be essential in a publication over ten pages long. The parts are listed in order of their proper sequence: Title page Copyright and printer's imprint Preface or foreword Acknowledgment

Table of contents Errata List of illustrations List of tables Introduction

4

AIDS TO TECHNICAL. WRITING

The one most often omitted from this list is the copyright. In the past very few tech:p.ical publications, other than books, have been copyrighted. The preface and acknowledgment may be combined, and the errata should be avoided. The introduction may be either a part of the preliminaries or of the text, and its position is determined by its nature. Ti:tle page-The title page will be repetition of some of the facts on the cover, with a few changes. The title of the book, the name of the author, and the name and address of the organization or institution sponsoring the publication are the necessary elements of the title page. Material may be centered, and no periods are used at the ends of lines on the title page. Copyright notice-When included, the copyright notice will appear on the back of the title page and the name of the printer will be placed on this page. If no copyright notice is filed, this page may be left blank, or may be used for the next part of the preliminaries. Although very few technical publications of the type under discussion have been copyrighted, any of them may be. Copyrighting is a simple matter and a precaution which should be taken whenever there is danger of statements being misquoted or twisted to suit a private purpose. In copyrighting, an "Application for Registration for Book Now First Published in the United States," two copies of the publication, and a registration fee of .$2 in money order form are mailed to the Register of Copyrights, Library of Congress, Washington, ·D.C. If you plan to copyright your work, have the printer include on the reverse side of the title page the regular form consisting of the · word "Copyright," the year date of publication, and legal name of the 'copyright owner. Preface and acknowledgment-The preface commonly follows the copyright notice on the recto page, but may be held over and inserted after the tables of contents and illustrations. The preface and acknowledgment may be combined. If the ackno~ledgment contai11s a long list of people or organizations, it should be ~rinted separately. . Table of contents-The table of contents lists the headings and pages of the main divisions in the book. :Frequently all subheadings are listed, indented under their proper division title. Such detailed listing may be necessary ip. a publication which is. going to be· used for reference, or in a publication on a highly technical subject which, however, may be partially usable by the layman. In a listing where subheadings are included, their relation to the main topic is shown by various degrees of indention, by grouping, or by a smaller type size. Lists of illustrations and tables-Under the "List of Illustrations" the drawings and photographs are compiled in the same form as the table of contents. Sometimes figures and photographs or plates merit division and separate listing. Tables are always listed separately. Dif-

PLANNING FOR THE PRINTER

ferent forms of numbering should be used to differentiate tables and figures, and if photographs do not fall within the category of figures then they may be left unnumbered. It is common practice to us~ Arabic numerals for figures and Roman numerals for tables. Paging-Small Roman numerals are used for the preliminary pages and Arabic numerals for the text. The page number is referred to technically by the printer as the "folio." It may be placed at the outer top margin of the page, on a line wit~ the running head, or centered . at the bottom of the page (sometimes in brackets). The :l:exi Organization and division of material with the aid of headings and subheadings is an important phase of technical publications. A confusing array of inconsistent titles destroys clarity. Wordy titles which repeat copy have a monotonous effect. Heads. and subheads act as an outline and guide while writing; butthey should be checked later for clarity and appropriateness. They, should be as brief as possible and should refer to the main topic under discussion. The size and position of headings should ·form a regular pattern throughout the publication. In brief technical publications, the chapter division may not· be used. Where it is used, the material for each chapter will begin on a new page. Roman numerals are used-. in preference to Arabic for chapter division. Where the chapter divi-. sion is not used, the same numbering practice may be used for new sections. A new section is not indicated by a new page, but by extra spacing between the copy. Reference ma:l:ter The most common addendum to a technical publication is the bibliography, but an appendix, notes, glossary, vocabulary, and index may be necessary. Rules for the style of a bibliography are given in Chapter IV, pages 18-22. It is unlikely that, for a brief technical pub- · lication dealing with one highly specific subject, a glossary, vocabulqry,· notes, or index will be called for; these are, therefore, not dealt with in any detail. · Appendix-An appendix is used for material not directly necessary to the conclusions of the text. It may contain special related problems, tables, charts, or other forms of associated discussion and detail. A division page is used to separate the appendix from the text. This is called a "half-title page" and in this case will contain only the cen-'.. tered word "Appendix." Page numbering in Arabic numerals is continued from the text. While no page numbers are _printed on the half- < title page, the page is counted as though numbered, and the first page,~: of the appendix copy begins with the succeeding number. ·'}k .

':)~

CHAPTER II

Style in Non-Letterpress Publications HEN the costs of a printed publication cannot be met, or when

the brevity of the copy does not merit producing a printed. bulW letin, the problem of publication may be answered by any one of a number of other processes. Mimeographing and lithographing processes have been used. The latter is known by various trade names among which are planographing, lithoprinting, and multolithing. All use the same basic process, although in some details equipment may differ. Photostating is a photographic form of reproduction and photogravure a gelatin process, both of which have special applications. These types of publications are referred to throughout this bulletin as non-letterpress publications. SPECIAL TYPEWRITERS

In setting up copy for such a publication, the author is his own editor. He must prepare and plan the makeup for his work so that the appearance will not be amateurish. He must be aware, first of all, of the limitations under which he will be working in the type of process which he chooses. With an ordinary typewriter, he cannot achieve a straight right-hand margin. A special typewriter is available which ' aligns the right-hand margin, and it requires very little training for a good typist to secure excellent results. Another form of typewriter has been produced which has varying styles of type. Such typewriters ·are usually run by skilled operators. The author may have the press which he chooses set up the final copy for him. In any case, his co-operation will be similar to that with the printer, although he may have more freedom in choosing his pattern of headings. Unless he is experienced in the artistry of the printed page, he should be cautious about makeup which does not follow standard procedures. Whatever process he chooses, the author should consult with the press which is to take care of the mechanics of publication and learn what limitations are placed upon him by the process, or what oppor.tunities he has for variety in his finished copy. For example, in planographing errors should not be erased, but may be covered with a piece of paper on which the corrected word is typed and which is pasted on the original sheet over the error. Reduction is possible with some ·of these processes; but care must be taken not to reduce the type size to a point where it is not clear. Firms which handle non-letterpress work usually issue instructions on the preparation of material.

NON-LETTERPRESS PUBLICATIONS

7

Careful choice of paper will add greatly to the appearance of the final publication. An opaque paper without stiffness will give the greatest satisfaction. All the previous rules for setting up material for printed publications are to be carefully observed; and it will be necessary that the author or the person to whom he delegates the final responsibility for the makeup of the publication be thoroughly versed in the order and style which the parts of the publication should have. No hard and fast rules can be set up for details of style in makeup. If they were, they would not be followed. But uniformity in style and form within a publication will secure a much better effect for the entire work. OUTLINE OF CONTENTS

Because of their brevity, technical papers or pamphlets may omit · a number of the formal requirements of a longer text. The only preliminary may be the title page, or the preliminaries may include table of contents, list of tables, list of illustrations, and acknowledgment. The author must decide upon the necessary elements and follow .the· printer's rules for pagination and makeup (see Chapter I, pages 2-5). The unprinted publication encounters its most stubborn obstacle in·. Inakeup. The type can only be varied from lower case, to lower case and caps, and to all caps. Underlining may be us~d to supplement these possibilities. Even with these narrow limitations, there is need· for standardization in usage. Se:tiing up the preliminaries Title page-The title page offers the greatest possibilities of variety,

and at the same time the greatest number of hazards. This page should contain the title, author's name-and usually the author's professional title unless this has been given on the cover, in which case repetition may not be desirable-the name of the institution or organization spon~ soring the publication, and the date of publication. It may also include the series number and classificati!)n, if the paper is one which falls into· a series. Variation of caps, and lower case and caps, may be done as. shown in Figures 4-7. Underlining is not desirable on the title page.. Because of the nature of the series into which this technical paper fell, it was considered advisable to include the series information on the title page even though it had been given on the cover. The date might have been placed below "Minneapolis", instead of in its present position. This publication was 8%"xll" in size-regular typing paper size-and not reduced from its original form. The inclusion of all these. details still left adequate white space. With the impossibility of reducing the size of type relative to the size of the paper, it is well to have less detail on a smaller page. Only the bare essentials should be given, as.shown in Figures 6 and 7.

Engineering Elq:e riment Station

Engineering Experiment Station

Technical Papo r

Technical Paper

llo. 45

llo. 45

DESIGII AIID P.I!ID'ORIIAIICE CHARACTERISTICS

OF A NEW TYPE ADHESIVE IIIPIIIGE!titiT DtET COUIITER

by

Frklk B. Rc.le,y, M.E. Professor an:! Director, Engineering Experiment Station

and

c.

Jordan, Ph.D. Associate Professor and Assistart. Director ~ineering _Experimert. Station ,

Riclllrd

September, 1943 Universi t;y of Minnesota Institute of Technolog;y Minne apolia

Figure 4. Standard Form for 8lh"xll" title page

DESIGII ANl PERFORIWICE CHARACTERISTICS

OF A

1m(

TYPE ADHESIVE IIIPIII.~~ Chapter IX, pages 38-39. .~

.

~ '

~.

'fJ '·"~

~·:~

'·;1

:,~ d

·i

'

'~ '(~

,:~ ·~;~

,··~ J~

~

''~

I

J

I..

~;(.;c,'·•,;,.i,:."~·'"i-~····,,~,~~---..:____ _ _ _ _ _..............,.......................,. .... ;}lil!t-:~~-···:·'4" OQilllll ..

r.·.;·..~'l~M"*+;~~:a;iiJ~W~ftti-.,ft~~'*f~1·1l~1r.r:\~*:~J?hilW~'~i~;~1·,r>i¥4j')r~MJiW\1\\iil)ilt£§WJ~*t:~ikN*i"']X\ ,,,_

r;'!>

Q ~~

{

~·>,

,_

CHAPTER ,IV

Bibliography Forms SOURCE material for a publication m-q,st be acknowledged by A LL the author. The usual method for this acknowledgment is in a formal bibliography in the reference matter following the text. In addition to its function of crediting other sources, the bibliography may be an aid to the student who wishes to look up further details on some one topic. In the case of publications treating more than one subject, bibliographies may be divided according to subject. Ordinarily technical bulletins and papers are highly concentrated and draw only on a single specialized group of sources. The usual form for a bibliography in a technical publication is a list alphabetized according to the surname of the author. A sample bibliography is given at the end of this chapter. Specific rules covering most frequently met types of citations are given in Table I, "Bibliography Forms." Special cases are listed in addition to the table, with methods for handling sources which deviate somewhat from the norm. In using Table I, simply check the first column for the type of publication which you wish to cite, and follow the example shown. If your source varies in some detail, look in the list of Special Cases under the type of item which you wish to check. Many variations are met with in forms for citation. The styles here listed were chosen for their simplicity and adaptability. The purpose of the bibliography will determine the form to be used. Since, however, the bibliography is always for the benefit of the reader, make sure that enough details are included to enable ~him to locate the source material if he wishes to do so. The number of pages is not always n~cessary. SPECIAL CASES (Listed in order in which they appear in citation) 1. Au:l:hor (a) If editor's or translator's names appear along with that of author on

title page, they should also be included in the citation: Kent, Williams. Kent's Mechanical Engineers' Handbook (Tenth Edition). Rewritten by Robert Thurston Kent (ed.) and staff of specialists. New York: ·.John Wiley & Sons, 1923. O'Neil, F. W. (ed.). Compressed Air Data: Handbook of Pneumatic Engineering Practice (Fourth Edition). New York: Compressed Air Magazine, 1934.

(b) If a compiler is given instead of an author, "camp." is placed in parentheses after the name: Wilczynski, E . .J. (comp.) and Slaught: H. E. (ed.). Logarithmic and Trigonometric Tables. Chicago: Allyn and Bacon, 1914.

Table I. Biblioqraphy Forms Type of Citation Book

Bulletin, Educational Institution

Items To Be Included Author or authors Title Edition, if other than first Place of publication Publisher Date Number of volume if more than one Author or authors Title Name of institution Series number Date Number of pages

Example (1) Day, D. T. A Handbook of the Petroleum Industry. New York: Chemical Catalog Company, 1926. (2) Rietschel, H. Heating and Ventilation: A Handbook for Architects and Engineers. Translated by C. W. Brabbee. New York: McGraw-Hill Book Company, 1927.

(1)

Rowley, F.· B., Algren, A. B., and Lund, C. E. Condensation of Moisture and Its Relation to Building Construction and Operation. University of Minnesota Engineering Experiment Station Bulletin No. 18, 1941. 69 pages.

(2) Proceedings of the Conference on Low Cost Housing Held at the Pennsyl-

vania State ColLege, April 16 and 17, 1936. Pennsylvania State College,

The School of Engineering Technical Bulletin No. 23, 1936. 103 pages. Government Document

Magazine articles

Author Title Series title (if any) Number of Congress and session if Congressional document Serial number (if any) Place of publication Date of publication Number. of pages Author Article title Publication title Volume number Series number Page numbers Date

(1) Hovde, M. R. Annual Meteorologi'cal Summary with Comparative Data. United States Department of Commerce Weather Bureau, Minneapolis, Minnesota, 1942. 8 pages. · (2) Climate of the State-Minnesota. Agricultural Yearbook Separate No. 1841. United States Department of Commerce, pp. 925-34. 1941. (3) Ingberg, S. H. and Mitchell, Nolan D. Fire Tests of Wood-and-Metal Framed Partitions, Building Materials and Structure Report BMS 71, U. S. Department of Commerce National Bureau of Standards, May 12, 1941. (1)

Bell, B. C., Jr. "Domestic Stoker Service." Coal-Heat, Vol. 42, No. 6, pp. 10, 12, 16. December, 1942.

(2) Shaw, Burton E. and Lyon, LaVerne. "A Study of Certain Factors that Affect the Droop Characteristics o~ Thermostats." Heating, Piping and Air Conditioning: ASHVE Journal Section, Vol. 11, No. 12, pp. 761-65. December, 1939. (Continued on next page)

Table I. Biblioqraphy Forms-Continued Type of Citation Newspaper

Items To Be Included

Example

Place of publication (if not included in title) Title Volume and series number Date of issue Section and page (for larger papers) Column number (for obscure items)

(1) Minneapolis Star Journal. CCXIV, September ,23, 1943, p. 7.

Non-letterpress publications (i.e. mimeographed, photoprinted, etc.)

Author Title Place of publication Method of publication Date Number of pages

(1) Watson, Cecil J. (ed.). Outline of Internal Medicine. Minneapolis: University of Minnesota Mimeograph Department. 1941. 102 pages.

Reference books

Title Place of publication Publishers Date

(1) Heating, Ventilating, Air Conditioning Guide. New York: American Society

Author Title Name of institution Series number Date Number of pages

(1) Nicholas, John E. The Characteristics of Electric Hot Air Dairy Utensil Sterilizers. Pennsylvania State College Agricultural Experiment Station Technical Paper No. 581. 1933.

Technical papers

Unpublished writings Author Title Classification Depository Date

(2) Baltimore. The Sun. Vol. 213, No. 111-D. September 22, 1943, p. 15.

of Heating and Ventilating Engineers. 1943. (2) Cole, G. D. H. "Socialism: Principles and Outlines." E7tcyclopaedia Britannica, 14th edition, XX: 888-95.

(1) Whittemore, E. R. "Insulation Board from a Variety of Cellulosic Farm Wastes." Unpublished M.S. thesis, Library, Iowa State College, Ames, Iowa. 1931. (2) Jones, L. D., President, Minnesota Creamery. Letter to A. R. Egglestein, Agricultural Experiment Station, University of Minnesota, Minn.eapolis, Minnesota, July 4, 1936.

p~,.Q)i¥¥.%iM.444J 1Wt~J,~t¥;6iijif@fu~~i·fl¥f UitilQJijJ4tUWM$f#i1l4iiii1 P.i •

1

l'r.

,

l

'

"-;!_~!t··~~~l:~~;r;:.~~-:z~~~~u~Mi~,:. iiz2~~~~g·~~~~~~~r~~~~i~~~;~~M~~~~~~~~~~~-.-~~~,~~~~~~~~~~d~:~~~~).-i~~~~~~;~~~.,iL:~~i~-.~~~-;~y_~~-~:.Ji!.~l~~

THIS IS A 500 TEMPLATE . .WITH LARGE PEN THIS IS A 500 TEMPLATE WITH 4 PEN THIS IS A 350 TEMPLATE WITH 4 PEN THIS IS A 350 TEMPLATE WITH 3 PEN THIS IS A 240 TEMPLATE WITH 3 PEN THIS IS A 240 TEMPLATE WITH 2 PEN THIS IS A 175 TEMPLATE WITH 2 PEN THIS IS A 175 TEMPLATE WITH I PEN THIS IS A 140 TEMPLATE WITH I PEN THIS IS A 140 TEMPLATE WITH 0 PEN THIS IS A 120 TEMPLATE WITH 0 PEN

THIS IS A 120 TEMPLATE WITH 00 PEN THIS IS A 100 TEMPLATE WITH 00 PEN THIS IS A 80 TEMPLATE WITH 00 PEN

Fjgure 30. One-half reduction of original lettering

THIS IS A 500 TEMPLATE WITH LARGE PEN THIS IS A 500 TEMPLATE WITH4PEN THIS IS A 350 TEMPLATE WITH 4 PEN THIS IS A 350 TEMPLATE WITH 3 PEN THIS IS A 240 TEMPLATE WITH 3 PEN THIS IS A 240 TEMPLATE WITH 2 PEN THIS IS A 175 TEMPLATE WITH 2 PEN THIS IS A 175 TEMPLATE WITH I PEN THIS IS A 140 TEMPLATE WITH I PEN THIS IS A 140 TEMPLATE WITH 0 PEN THIS IS A 120 TEMPLATE WITH 0 PEN THIS IS A 120 TEMPLATE WITH 00 PEN THIS IS A 100 TEMPLATE WITH 00 PEN THI518 A 80 TI!MPI..ATE WITHOOPEN

Figure 31. Two-thirds reduction of original lettering

PREPARATION OF DRAWINGS

81

Figure 27 is a full scale reproduction of vertical Gothic. lettering as made with LeRoy templates and pens, and the sizes of templates and pens indicated refer to LeRoy equipment. Table XII presents a comparison of the template and pen designations, the actual size of the lettering and the line weights for "LeRoy" 1 and for THIS IS A 500 TEMPLATE "Wrico" 2 equipment, thus enWITH LARGE PEN abling translation between THIS IS A 500· TEMPLATE these two types of lettering WITH4PEN guides. THIS IS A 350 TEMPLATE WITH 4 PEN Figure 28 is the same as THIS IS A 350 TEMPLATE WITH 3 PEN THIS IS A 240 TEMPLATE WITH 3 PEN the full scaled Figure 27 but THIS IS A 240 TEMPLATE WITH 2 PEN with a one-fourth reductionthat is, the linear dimensions of Figure 28 are 75 per cent of those of Figure 27. Figures' 29, 30, 31, and 32 are also the Figure 32. Three-fourths reduction same as Figure 27, but with reductions of one third, one half, two thirds, and three fourths, respectively. Thus, if the approximate reduction required is known, it is possible by means of these charts to observe the actual size in which lettering from standard templates and pens will appear. Figure 33 presents a chart showing the appearance of full size lines of various thickness and printer's designation. Figures 34, 35, 36, 37, and 38 show the same chart reduced one fourth, one third, one hal~,. THIS IS A 175 TEMPLATE WITH 2 PEN THIS IS A 175 TEMPLATE WITH I PEN THIS IS A 140 TEMPLATE WITH I PEN TKIS 1$ A 140 TEMP\..ATE WITH 0 PEM THIS II A 120 TUIPLU[ WITH 0 PEN THISISA120 TEMPLATE WITHOOPEN T141SISAI00TlJIII"I..t.TlWITH0011'£N fiiiiii .. IOT'l•I'!.'UWITMOO'IIt

Table XIII. Minimum Letter Heights for Satisfactory Legibility on Drawings Prepared for Reproduction

Reduction

Full Scale 114 Reduction 1/3 Reduction 1/2 Reduction %Reduction 3A Reduction

Ratio: Original drawing Reduced drawing 1:1 11/3:1 11/2:1 2:1 3:1 4:1

Minimum Height Letter Required on Original Drawing, Inches ·

Designation of Lettering Guide

Recommended Pen Size

Freehand lettering

Commercial lettering guide

LeRoy

Wrico

LeRoy

.049 .066 .074 .099 .148 .197

.039 .052 .058 .079 .118 .158

80 80 80 100 120 175

90 90 90 120 120 175

00 00 00 00

7 7 7 7

0 1 or 2

7 6 or 5

Wrico

two thirds, and three fourths, respectively. Again, by means of this· series of charts, it is possible to observe the appearance of a definite,· weight of line on the original drawing when reduced to the size desired for publication. Manufactured by Keuffel and Esser Company, New York, N. Y. s Manufactured by Wood-Regan Instrument Company, New York, N. Y.

1

82

AIDS TO TECHNICAL WRITING

LINE

LINE WIDTHS INCHES

IIZ50 IN.

.0040 IN.

1/200

.0050

1/150

.0067

1/143

.0070

1/100

.0100

1/80

.0125

1171

.0140

1/60

.0167

1/50

.0200

1/48

.0210

1/40

.0250

1136'

.0280

1/30

.0333

1/29

PRINTER'S DESIGNATION

1/2

POINT

POINT

I 112

POINTS

2

POINTS

.0350

2 112

POINTS

1/24

.0420

3.

POINTS

1/20

.0500

1/16

.0625

Figure 33. Guide for line reduction. Full-scale reproduction

In determining the size of lettering required for minimum legibility on a drawing for publication, it has been found desirable to make use of the ratio 3 Height of letter Distance from eye to printed page

I

It is recommended that in the use of commercial lettering guides such as "LeRoy" and "Wrico" this ratio be approximately 1/250, whereas with freehand slant lettering the ratio~ should be in the order of 1/200. a Hanscom,

"New Standard Aids Legibility in Engineering Graphs," Industrial Stand-

ardization, September, 1943.

PREPARATION OF DRAWINGS

LINE

LINE WIDTHS INCHES

11150 IN.

.0040 IN.

11200

.0010

PRINTER'S DESIGNATION

LINE WIDTitS INCHES

LINE

11150

.0017

1/IG

.0070

11100

IIIIOIN. •00401N. 1/2

POINT

.0100

11100

.0060

VIIO

·-

11141 1110

.0125

1171

.0140

1/100

1110

Dll7

1150

.0200

1141

,0210

1140

.0250

1131

.0210

I/ SO

I 112

POINTS

POINTS

1180

.011!1

1/71

.0140

1110

.1)117

1110

.0100

1/41

.OliO

1-'40

.0210

1/M

.oeto

1/30

I'Oifllll'l

1129

.0350

1/24

0420

1/20

.0500

1/10

1/lt

.01211

1/11

2 112

1/ft

I..INE WIDTHS INCHES

PaNTS

1/24

·-··-

,0420

.ceoo

Figure 35. One-third reduction

PRt,.rER's OfSHINATION

-

Figure 36. One-half reduction

.0100

POINT

.0333

Figure 34. One-fourth reduction

,0067

Figure 37. Two-thirds reduction

84

AIDS TO TECHNICAL WRITING

Based on.these ratios of "letter height" to "distance from eye to printed page" of 1/250 when using commercial lettering guides and 1/200 when using hand lettering, Table XIII has been prepared as an aid to choosing the correct lettering guide for various degrees of reduction. In calculati:p.g this table, a distance of 25 em has been assumed as the minimum to which the average eye can accommodate without undue eyestrain. This table indicates the minimum size lettering necessary to satisfy legibility when various degrees of reduction are contemplated. In many cases it will, of course, be found that larger lettering is desirable.

CHAPTER XV

Graphical Symbols S IN the case of standards· for letter symbols, the American A Standards Association has done much worthwhile work in the standardization of graphical symbols for technical publications. In the formation of these standards, they have had the co-operation of such national organizations as the American Society of Mechanical Engi- , neers, the American Institute of Electrical Engineers, the American Society of Heating and Ventilating Engineers, the American Welding Society, the Air Conditioning and Refrigerating Machinery Association, the National Association of Master Plumbers, the American Institute of Architects, the National Electrical Contractors Association, and others. Again it is highly recommended that in the preparation of·, any drawings for technical publications, wherever possible the American Standard Symbols be adopted. Up to the present ti:rt:le, the follow;.· ing publications on graphical symbols are available through the American Standards Association: · Graphical Eledrical Symbols for Architectural Plans, ASA Z32.9, approved 1943. Graphical Symbols for Power, Control and Measurement, ASA Z32.3, approved 1943. Graphical Symbols for Use on Drawings in Mechanical Engineering, ASA Z32.2, approved 1941. Graphical Symbols Used for Electric Traction Including Railway Signaling, ASA Z10g5, approved 1933. Symbols for Telephone, Telegraph, and Radio Use, ASA Z32.5, approved. 1942. Welding Symbols and Instructions for Their Use, ASA Z32.1, approved 1942.

It is impossible in a publication of this scope to reproduce com~· pletely all the graphical symbols which have been standardized for technical publications; however, most of the American Standards graphical symbols applying to the field of mechanical engineering have been here reproduced as indicative of available material of this, nature. For the most part the symbols here shown have been taken with permission from the publication "Graphical Symbols for use on Drawings in Mechanical Engineering," ASA Z32.2, approved 1941.

86

AIDS TO TECHNICAL WRITING

For reference purposes, a subindex is presented of the classifications of symbols shown in the following pages: Classification of Graphical Symbols

Symbols for Section Lining and Outside Views.................................................................. Plumbing ........................................................................................................................................................................ Plumbing Piping ....................................................................................................................................................... Pipe Fittings and Valves................................................................................................................................. Heating and Ventilating................................................................................................................................. Heating Piping ......................................................................................................................................................... Air Conditioning Piping ................................................................................................................................. Ductwork .......................................................................................................................................................... :................ Heat-Power Apparatus ............................................................................................................................... Refrigerating ............................................................................................................................................................. Conventional Rivets ............................................................................................................................................. Welding ..............................................................................................................................................................................

Page

87 88 91 92 96 97 97 98 100 101 103 104

GRAPHICAL SYMBOLS

SOUND OR HEAT INSULATION. CORK,HAIR-FELT, ASBESTOS, WOOL,MAGNESIA,PACKING, ETC.

CAST IRON

r--- ~ ,.--- ,---- - - ,.......--J ,----J --

~

..-----

~

~

~---­ ~ ,....+--

~,.-,..-...-'~

FLEXIBLE MATERIAL FABRIC,FELT,RUBBER, ETC.

STEEL

FIRE BRICK AND REFRACTORY MATERIALS

BRONZE,BRASS,COP'PER AND COMPOSITIONS

1111111111111111111

CONCRETE

_, 1-

BRICK OR STONE MASONRY

~·

ELECTRIC WINDINGS, ELECTRO MAGNETS, RESISTANCE. ETC.

WHITE METAL,BABBITT, ZINC,LEAD AND ALLOYS

ALUMINUM AND ALUMINUM ALLOYS

ELECTRIC INSULATION, BAKELITE,FIBRE,MICA,ETC. SHOW SOLID FOR NARROW SECTIONS

BRICK

SAND

WATER AND OTHER LIQUIDS

ACROSS GRAIN} WITH GRAIN WOOD

SYMBOLS FOR SECTION LINING

UNCOURSED AND COURSED RUBBLE

TRANSPARENT MATERIAL GLASS,CELLULOID,ETC.

ASHLAR

WOOD

SYMBOLS FOR OUTSIDE VIEWS Figure 39. Symbols for section lining and outside views

AIDS TO TECHNICAL WRITING

88

CORNER

BATH

lq

OVERHEAD GANG

SHOWER

eee (PLAN)

6 66 (ELEV.)

RECESSED

BATH

ROLL RIM

SITZ

FOOT

BATH

BATH

BATH

BIDET

SHOWER

SHOWER

STALL

HEAD

~ ~

~11

lDf

IT 1f 1!1~

6 T (PLAN)

[ill

PEDESTAL LAVATORY

PL

WALL

LAVATORY

1Qf WL

CORNER

~

LAVATORY

MANICURE

LAVATORY

MEDICAL

LAVATORY

[QJ ML

DENTAL

\Q)

LAVATORY

DL

PLAIN SINK

KITCHEN

KITCHEN R

a

SINK

L DRAIN BOARDS

(ELEV.)

Figure 40. Symbols for plum})ing

II

0

s

I

l~l

GRAPHICAL SYMBOLS

KITCHEN

51 NK

L. H. DRAIN BOARD

COMBINATION SINK AND DISHWASHER

89

I I§LJol I~

COMBINATION SINK A NO LAUNDRY TRAY

SERVICE

WATER CLOSET ("0 TANK)

URINAL (PEDESTAL TYPE l

G

URINAL (WALL TYPE)

SINK URINAL (CORNER TYPE l

WASH SINK (WALL TYPE)

11 1 URINAL (STALL TYPE)

WASH

SINK URINAL (TROUGH TYPE l

LAUNDRY

TRAY

WATER CLOSET (LOW TANK)

I I

DRINKING FOUNTAIN (PEDESTAL TYPE)

DRINKING FOUNTAIN (WALL TYPE)

Figure 41. Symbols for plumbing

lol

. AIDS TO TECHNICAL WRITING

90

DRINKING FOUNTAIN (TROUGH TYPE )

loool

DRAIN

D

OF

D

HOT

WATER

WATER

TANK

HEATER

(!)

GREASE

8

OIL

SEPERATOR

SEPERATOR

CLEAN OUT

~

[BJ

r-Q--1

METER

~

M

HOSE

lo

RACK

GARAGE

~

DRAIN

HR

HOSE

FAUCET

T

FLOOR

DRAIN

BACKWATER

WITH VALVE

if

HF

GAS

OUTLET

T

ROOF

G

VACUUM

OUTLET

v Figure 42. Symbols for plumbing

SUMP

[J

GRAPHICAL SYMBOLS

91

PLUMBING SOIL ,WASTE OR LEADER (ABOVE GRADE) SOIL,WASTE ORLEADER(BELOW GRADE) - - - - VENT

-

-

-

-

-

-

COLDWATER

--------

HOT WATER

-

-

---

----- - - ~--

HOT WATER RETURN FIRE LINE

- - - F - -.....- - - F - - -

GAS

---G

G--ACID

ACID WASTE DRINKING WATER FLOW ORINKING WATER RETURN VACUUM CLEANING COMPRESSED AIR

----v ------v ---

_____._A------

SPRINKLERS MAIN SUPPLIES

------ s ------

BRANCH AND HEAD

-s---s-

DRAIN

PNEUMATIC TUBES TUBE RUNS Figure 43. Plumbing, sprinkler, and pneumatic piping symbols

AIDS TO TECHNICAL WRITING

92

FLANGED

JOINT

SCREWED

WELDED

c

II

IJ