: How were scientific illustrations made before the spread of digital computers? Before the advent of digital computers, a lot of scientific publications had high quality illustrations. How did they

@Samaraweera207

Ho-ho, the book is dated 1940!

Now look, back in those days and up to when computers started appearing "technical drawing" used to be an obligatory subject at high school (well, at least down here in Russia). They would teach you just how to handle those weird devices mentioned above, if you're up to becoming an engineer.

1) Things used to be drawn using a simple "ruling pen" (google it up) filled with ink.

2) In the 2nd part of the XXth century "rapidograph" appeared and made it a bit easier -- as much as rechargeable ink pen is better than the "dipping" one. Though precision is better with the ol ruling pen...

3) Linking "seamlessly" the ends of two curves drawn using those curve "rules" shown above was proof of your drawing skill.
Now in the college of architecture one of the entering exams was technical drawing. The most tricky par was meeting ends of curves, those were checked with a magnifier by a teacher...

Back in the 80-s things were still drawn by hand -- at least student tasks. Most troublesome was "typing" the text in decently looking letters with a pen... You can see it on your illustrations, letters are hand-written.

As for books, I guess the author did the drawings himself. Back then a good engineer/specialist knew how to draw, that was part of the expertise.

Vote Up Vote Down

@Jamie315

The basic tools were, for students and small shops, drawing board, T-square, triangles (30-60-90 and 45-45-90 and sometimes adjustable-angle ones), pencils (non-repro blue was favorite since it didn't have to be erased, but black was used too), compass sets (center-wheel K&Es (Keuffel & Esser) and Dietzgens were probably favorite) and Rapidograph technical pens for lining around curves because the ruling pens in the compass sets didn't really want to go around curves and would blob. Erasers were important, both ruby for ink and kneaded for pencil. Most finished work was done in waterproof india ink.

Bigger shops used "drafting machines" (you can find them on ebay still) in place of the board, t-square, and triangles, but also the compass sets, pencils, Rapidographs, and erasers.

Depending on the industry, one might have a set of french curves and/or a spline / ship's curve set. Splines were more general because they could be shaped, but trickier to use because they could be re-shaped accidentally.

There were (still are, I suppose) standards for the types of crosshatching to indicate material, the angles and distances at which dimensions and legends were added, etc. The standards varied by industry.

Calculation was usually done with a slide rule.

Vote Up Vote Down

@Shelley591

Such artwork was generally referred to as "technical drawing" and was very much a part of the syllabus for all qualified "technicians" (ie. those attending formal training colleges) and also many graduate engineers.

If you just search for terms related to "manual technical drawing" and "manual draughting" you will find lots of stuff on the subject. Or start with these and then follow the links :

Wikipedia: "technical drawing", "technical drawing tool"

YouTube: "technical drawing", "french curve", etc

And some people do still do it the hard way:

Vote Up Vote Down

@Karen819

A lot of the old engineering books have a chapter on drawing - for example, I have "A textbook on Electric Lighting and railways" International Correspondence Schools, Scranton, PA, 1901; the first 100 pages or more are about technical drawing. We had to learn technical drawing in school (1970s UK).

One practical way to draw the lines on the graph is to mark as many points as possible in pencil and then fit a flexible French Curve to the points and use a ruling pen to draw along it; with practice you can also draw the lines freehand once you pencil it in lightly first, or use the edge of a brass (or, more recently, plastic) set of French Curves, as others have suggested.

Vote Up Vote Down

@Gail6891361

If you question is how they reproduced diagrams ad such in printed books: Engravings ("cuts"), originally prepared by hand and later via a photoresist etching process.

Vote Up Vote Down

@Radia289

How did they do this without computers?


They used rulers. If you exclusively know how to draw with a computer: that's a straight edged object, to help guide a pen or pencil into a straight line.

For really advanced technical drawings, such as the curve graph example, there were templates with different curves (elliptic, parabolic, hyperbolic):



There were even templates for the distinct type of lettering (to draw by hand). There were also rub-off sheets, for lettering as well as for standard symbols:


(image from www.smithdrafting.com; see there for loads more of these)

(Although it appears to me no template was used in your examples, as they both are lettered good but not perfectly.)

The hand drawn images can be cut and pasted onto text pages to fit, after which the entire page was photographed and used as-is, or, alternatively, the images could be photographed separately from the text and composited as negatives, just prior to transferring them to an offset plate. The latter was the preferred way of handling these where I started out, because often the quality of the images was wildly different from the plain (typeset) text. That way we could ensure an optimal contrast for both images and text.

Vote Up Vote Down

@Yeniel278

Engineers and scientists of different branches used to have drawing classes on their curriculum. Many of these people were quite accomplished at this.

We used to have row upon row of drawing boards in the classrooms in the design/engineering departments. The drawings were drawn with pencil and then inked for final results. They would then be reproduced on a etching on a pressing plate. Techniques were varies and include he photogravure, chromolithography, basically the image was photographed and then using projected with a light onto a light sensitive substrate that then protected the plate. Similar tech is used today for producing electrical circuits.

It still bothers me that many of these hand drawn images are actually better than what many produce today. Publishing decent quality images is easier today than ever in the past yet people can't use even that.

Vote Up Vote Down

@Holmes874

They hired illustrators to draw high quality illustrations using analog media such as markers and paint.

UPDATE:

Now that I see your examples, those are hand drawn mechanical engineering drawings. The technique is pencils, paper, straight edges, and mechanical measuring tools (rules, compasses, protractors, etc.)

Vote Up Vote Down