George Washington Richardson

By the beginning of the 20th Century, American-made slide rules had found their way into the marketplace, with fine mahogany slide rules being sold by the likes of Keuffel and Esser out of New York, and Eugene Dietzgen out of Chicago. But an experienced, entrepreneurial engineer in Chicago had an idea for making “a slide rule that would not be prohibitive by price, and also a book of instruction that the average person could comprehend” by making a slide rule out of stock metal and giving it a special feature to assist in its use. George Washington Richardson, a consulting engineer, developed and improved his “Direct Reading” slide rule over several years, creating a uniquely recognizable instrument.

What we know about Richardson is that he was born in about 1865, was a Navy veteran who served during the Spanish-American War in 1898, and was likely overseas in 1900, as we shall see below. He was a Chief Electrician in the Navy with a strong engineering aptitude. In 1901 Richardson, who by then was living in Chicago, enrolled in a course in Electrical Engineering through the International Correspondence Schools (I.C.S.), a popular long-distance technical school based in Scranton, Pennsylvania. He received his diploma in 1904. And it is at about this time where we begin to find mentions of George W. Richardson, and subsequently his slide rules, in Popular Mechanics magazine.

Below is an image of a 5-inch Direct Reading slide rule made by Richardson. It has a metal body and slide, with scales and text printed on celluloid and adhered to the metal. On the back of the rule is a table of “Problems” to solve; for example, to convert cubic inches to cubic feet, the table shows to set the “Scales Key” to O, find the value of cubic inches on the C scale, and read the value of cubic feet on the D scale. To set the Scales Key, move the slide until the red letter “O” appears centered in the “keyhole”:

We can see in the image that at the left index of the D scale is the value 12³ = 1728 on the C scale. This process of setting the slide at a “gauge mark” is unique to the Richardson slide rules.

I have a collection of about 10 or so Richardson slide rules and have never been sure of the particular years in which they were made or what was significant about the various models — other than, of course, that they were made in Chicago. There are patents on most, from 1911 and 1912, but the rules were sold for several years beyond that. Meanwhile, I’ve read in some of the slide rule literature that Richardson had advertised his slide rules in the magazine, Popular Mechanics. I remember finding this magazine interesting when I was a youngster, especially its articles on the possibilities of extraterrestrial life! When I started searching online I found that the early publications of Popular Mechanics (PM) had been scanned and were available to explore for free. So, I decided to go about searching them for anyone named “Richardson” to see if articles or advertisements might shed some light…

Popular Mechanics, a periodical established in 1902 by Henry Haven Windsor, was being published in Chicago until 1962, when its operation was moved to New York City. It is still being published today. Scanning through the earliest copies of PM, the first mention I found of George W. Richardson was in 1904. On page 702 of the July, 1904, issue of Volume 6 an image (shown below) is reproduced which is captioned, “The Fighting Fleets of the World Assembled in China Waters 1900.” The story notes that,

“The illustration is from a rare photograph in the possession of Geo. W. Richardson, of Chicago, who was chief electrician on the Brooklyn during the allied demonstration. The original picture was worked on silk by a Japanese artist who was on one of his country’s ships.”

It is not obvious how Richardson was originally connected to Popular Mechanics, though I can imagine that he might have written to, or directly interacted with, the magazine’s office in Chicago. He soon became an author of PM articles, and also placed ads in the magazine.

The first article I found written by Richardson for PM was in the September 1905 issue, in which he wrote a four-page article on the American diesel engine:

We glean from his opening sentence that he must have recently turned 40, and also find that he was invited to write this article by the magazine’s editor.

I also found the following ad placed by Richardson in the magazine that same year, through which he was essentially looking for consulting work:

The ad also lists his address at the end: 2181 W. 24^th Place, Chicago, Illinois.

In 1907 he was published once again, this time a two-page article on how to make an efficient “wireless telegraph”:

The same “Wanted” ad from 1906 was also placed in PM in 1907.

I searched through the Popular Mechanics issues of 1908 but found nothing from Richardson in that year.

The next occurrence I found of Geo. W. Richardson in PM came in the April 1909 issue, where he was again searching for consulting work, but with a new ad:

Then, finally, just a few months later, came the first mention of a slide rule, in PM Sept. 1909:

He immediately claims that “it was invented a half century ago…”, which I can only imagine is reference to the Mannheim design of the slide rule. He notes how slide rule prices have been ranging from $4-$5 and that their instruction manuals were too technically detailed for “the average mechanic, engineer, or business man to comprehend.” His new Aluminum rule, on the other hand, including a book of instructions, was selling for only $1.50. At the end of the ad is his name and home address — 4212 24^th Place, Chicago.

It turns out that Richardson had just filed a patent application on August 26, 1909 (eventually granted in 1911), only weeks before the above PM ad had appeared. The patent covers primarily his implementation of gauge marks, but also discusses the design for the connecting of a metal cursor onto his metal rule. The general shape of the cursor is not specified, only how its edges are to engage with the metal stock of the slide rule. And notice that his ad above does not show a cursor on the slide rule.

Here is my earliest example of a Richardson slide rule, likely from about this time:

On the back was his table of “problems” containing the appropriate setting of the gauge mark in the “Keyhole” to use for that problem. Note that this rule has an interesting cursor, though no cursor is shown in the 1909 advertisement. Its special “waist” holds a glass with two hairlines, one on each side of the waist, so as to be able to make readings near either edge of the rule. (I looked to see if the spacing of the hairlines had any particular significance, such as a multiplication to perform a change of units, etc., but I haven’t found a viable meaning yet.) Also, the glass and its hairlines are rather short and do not easily reach the A and D scales to be fully effective. It was almost as though this cursor design was an afterthought. One also can see the words “PAT APPLD FOR” at the top of the cursor. The slide of the rule is made of stiff reinforced celluloid, while the stock of the rule is Aluminum with celluloid adhered to its front face. At the end of the instructions on the back we find, “Copyright 1909 by George W. Richardson.”

The following image is of my second example of the same slide rule, with the same cursor, but with the words “Pat. Appl’d For” stamped near the top-right end of the slide rule body. It appears to me that it could have been added after the primary construction of the rule.

Richardson also authored a short “snippet” in the same PM Sept 1909 issue:

He had no doubt learned a few tricks over the years when it came to snipping pieces of heavy metal in his basement.

I found at The International Slide Rule Museum a copy of Richardson’s Instruction Book (autographed on the inside cover!), with a copyright from 1909:

It shows the same slide rule image on the cover, again with no cursor.

After further searching, I found that, over a year later, Richardson appears again in PM, this time in their Dec. 1910 issue:

And in the same issue, we see his next slide rule advertisement:

This is the first image I found with his interesting early cursor. So we now know this cursor was being used by sometime in 1910, but still could have been created by late 1909. The body and slide are the same as shown in the 1909 advertisement, made of stock Aluminum, and we know from the 1909 patent application that he had already been working on the implementation of a cursor.

Also of note is that his address changed from 4212 to 4215 24^th Place.

As my second early Richardson rule has “Pat Appl’d For” stamped on it, I conclude that it was from between late 1909 and 1910. The other rule, without the stamped patent information on it, was earlier, likely 1909.

About a month or so after the above ad made its appearance in PM, Richardson’s patent, applied for in 1909, was granted on January 31, 1911.

Within a couple of months, on April 3, 1911, Richardson applied for yet another patent, this time concentrating on his new metal slide which would replace the original celluloid slide, along with an appropriate cursor for the new construction.

An image of his new rule appears six months later in Popular Mechanics, when we see the following ad appear in the issue of May 1911:

And here we see a much more conventional-style cursor on the slide rule, with a single full-length hairline. The text says, “ ‘See sectional cut’ curved slide bound with aluminum. No other like it.” This is referring to his new slide design, for which he had just submitted his new patent application.

So, at this time, Richardson has a new slide rule with a metal stock and metal slide, scales printed — with two colors! — on celluloid attached to the metal, and a new full-hairline metal cursor, accomplishing an impressive amount of individual design and engineering in a relatively short time, especially for someone working out of his basement. And note that his basement must have moved yet again, this time to 4218 24^th Place.

With a solid slide rule now being manufactured, and a new patent in the works, his advertising in the issues of Popular Mechanics became a bit more frequent. The images shown below are examples of ads that appeared repeatedly in a number of issues over the next 12 months or so.

PM June 1911:

PM Aug 1911:

At the end of the ad, he notes that, “A limited number of new, but older pattern rules at $1.00 each” are available for sale.

PM Mar. 1912:

Note: Richardson’s aforementioned second patent was granted on March 26, 1912 just after the release of this last ad publication.

You can see in the ad above that he is now referring to his slide rules by the year in which they are first marketed — the text above refers to his “1912 type” slide rule. It also notes that his rule is made of “non-corrodible nickel steel.” It also mentions that he now has a “Five-5-inch Rule”, …, “vest pocket size, in leather case.” An example is shown below of his 5-inch version, and it has the new cursor and a 1911 patent on the rule. The 1912 patent is found on the cursor:

In the well of the rule he has the 1911 patent stamped, but also it says, “OTHERS-PENDG.” So when the 1912 patent came out in March, he started stamping it on the cursors. Sales evidently were going smoothly enough, that at some point the same rule was being made with both patents printed on the body:

Another important element of the above advertisement was its introduction of Richardson’s new book, The Slide Rule Simplified. This book would replace the much shorter set of instructions he had with his previous slide rules, and would go through several revised editions over the next several years.

And by the way, if one looks at the bottom of the title page in his new book, he shows his earlier address, at 4212, rather than the latest address, 4218 24^th Place:

Another year passes and then we find a new ad in PM June 1913:

He calls this his “1913 type” slide rule in the text, and it is now made of “non-corrodible Aluminum and Monel Metal.” Notice that its cursor is of a slightly different form than before — the indentations on the top and bottom are missing, and two rivets appear on the front face. The new rule also has sine, log, and tan scales, which is mentioned in the text but which are not shown in the image in the ad. An image of one that I have found is shown here:

Then, at the end of the year, in PM Dec 1913, we find the interesting headline:

The artwork looks essentially the same as in the previous image, but the slide rule scales being discussed are slightly different, and yet are not shown in the image. He calls this his “1914 type now on the market for the first time” and only Monel Metal is mentioned, not Aluminum.

His talk about addition and subtraction on the slide rule is certainly striking. This is accomplished by adding a second log scale (L scale) between the B and C scales on the slide, which can be used in conjunction with the other L scale located at the bottom of the rule to add numbers together — a slide rule that can do it all.

This feature of having two L scales continues to be discussed in future ads, though none of the artwork I’ve seen in PM show the actual rule being discussed. An image is shown below from the ISRM of the same model, here labeled as Model 1812, where you can see the additional log scale located in the middle of the slide (labeled “±”), which is to be used in conjunction with the “LOG” scale at the bottom:

You may notice the all-plastic cursor in this image, indicating that it came a bit later than the time period we are talking about. I actually found an example of the earlier version, with the metal cursor as shown in the advertisement and with no model number, on Facebook Marketplace just a few weeks ago in Illinois. Unfortunately it had already been given away to someone else, and its image was removed from Facebook before I could grab a copy. We’ll come back shortly to the version with the plastic cursor, shown above.

A new version of the ad appears in PM Apr 1914:

Again, there is no “L” scale on the slide in the image, but by this time it is apparent that Richardson was making slide rules with a variety of scales, and rules of different lengths (5 and 10 inches), though these features are typically not shown in the images in Popular Mechanics.

Searching through issues of PM in 1915 we see no mention of Richardson.

Then in PM May 1916, we find in the advertisements section of the magazine, an ad offering a free slide rule with each copy of his book:

Here, the address is 4210 W. 24^th Place, a bit down the street in the other direction. He has by now occupied (perhaps simultaneously) the addresses 4210, 4212, 4215, and 4218 W. 24^th Place.1

One month earlier, on April 4 , 1916, Richardson had applied for his third patent, this time for new improvements to the spring-form interfacing between the slide and the slide rule body. This patent would be granted two years later.

Of relevance, in April 1917 the U.S. joined the Allies in the Great War (WWI).

We next see Richardson return to PM in the October 1917 issue:

This is an ad for his Pantocrat system, where several interchangeable slides were available for a wide range of different scales and applications. One could buy the entire system, as indicated in the ad above, or order particular slides or sets of slides. The online image of the ad, which is hard to read, only states that the rule is made of metal. And, the cursor is by now an all-plastic design. One example I have came with a box that was labeled “Pantocrat”. It has only one slide and is labeled with Model number 812:

The 812 is obviously a Mannheim scale arrangement, with S, T, and L scales on the front.

Earlier we showed an image from the ISRM web site of a rule with the “+/-” scale on the slide. Looking back at that image, one can see it is actually from the “Pantocrat” series, with a plastic cursor. However, the model number shown on its slide is “1812”, while the original slide rule that had the “+/-” scale was simply referred to as the “1914”-type rule.

Another example I have came with two separate and different slides, one with an added CI scale (which has the 1776 label) and the other with three Log-Log scales (labeled as Model 1860 LL). It also has a K scale at the top:

Below we see another Model 1776, taken from the ISRM web site. Notice that the fonts are different on some of the scales, particularly noticeable on the CI scale. I’m not sure about the difference in timing for these two different fonts.

One can tell the difference between the Pantocrat slide rules and their earlier counterparts (“type 1913”, “type 1914”, for example) by the slides. The later Pantocrat rules have a raised indentation along the center of the slide, while the earlier models are simply smooth arcs across the face of the slide:

The raised indentation is a feature described in the patent application of 1916.

Note that on 1776 models there is no room to indicate the maker of the rule on the front. In particular, a K scale has been added at the top of the rule. References to Richardson are made on the slides and are only visible when the slide is removed.

On the Pantocrat models that I’ve seen, one finds the words “Richardson Rule Works”, as opposed to “Richardson’s Direct Reading Slide Rule,” or variations thereof. I have seen no reference to “Richardson Rule Works” in any of the ads nor in any versions of The Slide Rule Simplified. I have not found a date for when “Richardson Rule Works” might have become the official name of his company, but this label has not appeared on any images I’ve seen of slide rules prior to the 1917 Pantocrat system. Perhaps this suggests that Richardson had outgrown his basement by now, which is quite likely. More on that in a moment.

Richardson was not mentioned again in PM after 1917. (I stopped my searching of his name in PM beyond 1921.) I have never seen any information in the slide rule literature suggesting that he advertised in other periodicals, though a quick search online shows that he did; it would be interesting to research this further.2

One example of relevance, post-1917, that I did find was the following:

This was found in the Journal of the United States Artillery, from first-quarter 1918.3

Though no longer taking out ads in Popular Mechanics in 1918 or 1919, Richardson nonetheless was active. His new venture during this time period was with a new slide rule that was developed for use by the U.S. Military in the on-going war effort. A short note appears in the magazine, The Iron Age, on page 1340 of the May 23, 1918 issue:

The new slide rule, manufactured by Richardson for J.H. Weil and Co. of Philadelphia, was dubbed the “Model 1917” and was of a very different type of construction. A general artillery slide rule for triangulation, much akin to the K&E Short Base Triangulation Slide Rule, the Model 1917 is made of Mexican mahogany with a celluloid face, and has a brass backing.

As can be seen, this is very atypical of a by-now standard Richardson metal slide rule, but it also presented Richardson with a military contract of an expensive instrument which no doubt was a lucrative business opportunity for him. Perhaps a government contract was what facilitated the need for a more formal business entity, such as, say, “Richardson Rule Works”.

Richardson’s book, The Slide Rule Simplified, went through a number of editions between 1912 and 1918. Text for its sixth edition was copyrighted in early 1918, and this edition has a 12-page feature section on the use of the “Military Slide Rule” located at the back of the book. This special section was authored by a mechanical engineer named John Jesse Clark of Lehigh University.

Interestingly, through my online searches I was able to find that John Jesse (J.J.) Clark received his M.E. degree from Lehigh University in 1888. According to Lehigh’s Alumni Association report of 1895-96, he was at that time Chief Instructor in Mathematics and Mechanics at The International Correspondence Schools.4 This was the school from which Richardson had performed his long-distance technical studies from 1901-1904. Clark was also Associate Editor of Home Study magazine, a publication from Colliery Engineer Co., in Scranton, Pennsylvania. And by the time Richardson was studying through I.C.S., Clark had become the Dean of Faculty for the school.5 ^,6 It is quite possible that Richardson corresponded with Clark while enrolled during those years, since Clark taught mathematics and mechanics.

Clark also had an interest in slide rules, having written a textbook on the subject, with a copyright date of 1909.7 I have a copy of this text, and one can also find an online copy as well. At the end of the 62 pages of text in my copy, there is a two-page plate of images for Figures 2, 3, 5, and 6. The right-side of the plate is torn and partially missing. However, we can read the captions and can see that these images are of the front of a Mannheim slide rule (referenced on page 12), the back of the rule showing a table of constants (referenced on page 54), a 5-inch Mannheim slide rule (referenced on page 58), and a Reitz rule (referenced on page 59), respectively.

However, in the online copy of the book, this set of images is missing, even though the figures are referred to in the text, which is identical in both copies. But, at the very end of this particular copy, in place of the set of images we find the following ad:

Now, doesn’t that cursor — on an aluminum frame stamped from one piece of metal, with heavy white celluloid facing — look familiar??? (See section 1913-1915, above.) It is hard to know exactly when this book was printed. Both books show the same 1909 copyright date, but this is not the same as a printing date. It is quite possible that this printing is from the 1913-15 time frame or later. The only other difference I have been able to thus far discern between these two copies of The Slide Rule, by Clark, is that my copy was published by Technical Supply Company, Scranton PA, and New York, while the online version was published by Technical Supply Company, Scranton, PA.

All of this is highly suggestive that the I.C.S. could have been offering slide rules from its former student with copies of Clark’s book. Again, we will come back to this later. For now, let’s get back to the Model 1917, and its description in The Slide Rule Simplified.

The caption in the figure on page 90, above, refers to the slide rule as Model 1917. Note that the article’s title shows a 1918 Copyright by Geo. W. Richardson. This will be particularly interesting when we look at the next edition of The Slide Rule Simplified in a moment.

The Model 1917 slide rule performs the basic triangulation calculation, though in a slightly different way as was seen on the K&E Short Base Triangulation slide rule. The scales on Richardson’s rule are referred to as A, B, C, and D. The A and D are each single-decade logarithmic scales, while B and C are scales for the sine function, where the angles are in units of military “mils”. (1600 mils = 90^o.) The B and C scales run right to left, and thus are “inverse” scales. The procedure is to solve for the range R = b sinA/sin t, with definitions used in our SBT discussion. The ratio b/(1/sin A) is set on the upper scales, and then one searches for R opposite (1/sin t) using the lower scales. Notice that the use of inverted trig scales is similar to their application used in the Crichlow-style slide rules discussed in an earlier post, which was still being used just prior to the Second World War.

As an example, let’s solve for the range R, given a base b = 200 yd, A = 700 mils, and t = 35 mils, to find R = 3690 yd. We set 700 mils on B against 200 (i.e., 2) on A. We then find opposite 35 mils on C, our Range 3690 on D:

In the article written by Clark for the sixth edition of The Slide Rule Simplified (1918), the going rate for this Model 1917 was $20, compared to Richardson’s most expensive offer within his metal slide rule offerings — the complete interchangeable 6-slide Pantocrat system with leather case and 100-page book, which sold for a total of $10.

By the way, Richardson’s third and final slide rule patent, that was applied for in 1916, was granted on March 26, 1918.

And it was in November 1918 when WWI came to an end.

And then there’s this tidbit: On the title page of the 1918 sixth edition of The Slide Rule Simplified a new address is given for George Washington Richardson — note, not George W. Richardson any longer. Rather than one of his “24^th Place” addresses, the new address is in downtown Chicago, just west of the Chicago River, near where the Ogilvie train station now exists:

The selling of Military rules to the U.S. Government must have created a big turning point in the life of George Richardson. It had to be a large production and a much different manufacturing process for him; and very likely much more lucrative. It would be fascinating to learn what led to Richardson becoming the manufacturer of the Model 1917 during the war, and what he had to do to facilitate the venture. Perhaps there were connections between the Technical Supply Company and the International Correspondence Schools, both operating out of Scranton, Pennsylvania, and the J.H. Weil and Co. of Philadelphia, Pennsylvania.

It was not long after the end of the War that Richardson retired from the slide rule industry, reportedly selling his business to a slide rule colleague, Clair Gilson, in about 1919.8 There is no official notice of Richardson selling his company to Gilson, but much evidence suggests that he did.

Clair Gilson had been manufacturing slide rules — in his home’s basement, in Niles, Michigan, about 100 miles east of Richardson’s home — which also were being advertised in Popular Mechanics as early as 1917. His first circular slide rule had a copyright of 1915 and had scales on paper that were glued onto wood. He then went to paper scales on steel disks, then celluloid enamel on aluminum disks. It also incorporated two celluloid cursors. His next version of the “Midget” slide rule — his most popular version — was copyrighted in 1919 and had scales printed on white celluloid enamel on aluminum.9 Learning Richardson’s techniques and acquiring his equipment would have been a huge boost to the Gilson business. Some very nice discussions of the connection(s) between these two entrepreneurs can be found in the references at the end of this post.

One of those references, an article by Michael Konshak (See Further Reading, below), presents the following letter, which also can be found on the ISRM web site. The letter is from Richardson to the International Correspondence Schools in April 1920:

The letter is the source of our knowledge that he took I.C.S. courses from 1901 to 1904, and that he was 54 when he retired.

It is often mentioned that Gilson advertised Richardson slide rules, and it has been said that Richardson returned the favor. An often-quoted example is the advertisement of Gilson products at the back of the seventh edition of The Slide Rule Simplified, which can be found in pdf format, with hardcopies frequently for sale online.10 The ad for the Gilson Midget slide rule from the seventh edition is reproduced here:

This seventh (and final?) edition of the book is often quoted as being from 1918, as this is the last copyright date given in the front of the book. However, just under the title in the above image we read that the Midget was patented on January 17, 1922. So, this printing of Richardson’s book must be from 1922 at the earliest! The materials written by Richardson and Clark were written separately by the two, and all had been previously copyrighted in 1918 by Richardson for the sixth edition of The Slide Rule Simplified. But since the business was by now sold to Gilson, the book evidently was re-issued in 1922 using the material from 1918, citing both gentlemen as co-authors. One thing that was completely new in the book was all of the Gilson ads at the end. Also of note, we find that the (presumably) 1922 seventh edition was being published by Technical Supply Company, in Scranton, Pennsylvania.

Other interesting details can be gleaned from going through some of the other material in the back of the seventh edition. These include:

• The text regarding the Model 1917 is no longer included in the seventh edition.

• On page 66 we see an article entitled, “DIRECTIONS for using the Richardson Polymetric Slide Rule, No. 1776”, which is written by J.J. Clark.

  • This article also appeared in the sixth edition; but there, we had “Copyright 1918 by Geo. W. Richardson.” In the seventh edition, we find “Copyright 1918 by Gilson Slide Rule Co.”.

• On page 72 we find the article “DIRECTIONS for using the Richardson Log-Log Slide Rule No. 1860 LL”, also by Clark.

  • This article was also found in the sixth edition, though the title had the word “Logometric” instead of the phrase “Log-Log”. Again, the 1918 copyright is changed to “Gilson”.

• On page 82 are “DIRECTIONS for using the Richardson Binary Polymetric Slide Rule 1865-O”, by Clark, and also 1918 copyright by Gilson.

  • So perhaps 1918 was the actual year in which Gilson purchased Richardson Rule Works, taking over the copyrights for J.J. Clark’s writings.

• There is also a short article, “CO-MULTIPLICATION,” written by S. J. MacFarren, Washington, D .C., with “Copyright 1920”, further substantiating that the seventh edition is not from 1918.

• Starting on page 92, we see a 3-page description of the Richardson Direct Reading Slide Rules, which helps interpret the model numbers that have been presented in today’s post:

  • 812 — Mannheim

  • 1812 — Add and Subtract

  • 1776 — Polymetric (includes CI scale)

  • 1860 L-L — Log-Log

  • 1860 — Business Man’s Slide Rule

  • 1901 — 5-inch version of the Polymetric

  • 1865-O — Binary (an inspiration for the Gilson Binary, perhaps?)

  • Pantocrat Six-in-One — One complete rule plus 5 extra slides; i.e., one 10-inch slide rule body plus all of the above 10-inch slides

There are a few other interesting things for sale in the back of the book as well, including the Gilson Atlas slide rule.

And, finally, the Konshak article also shows an example of a physical version of the sixth edition (note, not the seventh edition) which shows Gilson as the publisher on the title page, although Richardson is still listed for the 1918 copyright.

So, it appears that Gilson could have acquired Richardson’s business in 1918, and certainly by 1919, and that Gilson indeed continued to sell Richardson slide rules and copies of The Slide Rule Simplified after acquiring the company, at least for a few years, and perhaps for quite a few. An article by Bruce Babcock in JOS shows that at one time the I.C.S. was offering free copies of The Slide Rule Simplified to their students who could sign up another student to take a course.11 This was a similar scheme as that found earlier in Clark’s book with copyright 1909, which may have been re-printed in 1913-15. But this new offer noted by Babcock was being advertised in 1928!

Since The Slide Rule Simplified is a more comprehensive text (90 pages and heavily illustrated) than J.J. Clark’s 1909 The Slide Rule, it appears that the I.C.S. likely was using the latter in the mid-teens and then switched to the former in the 1920s, after the sale to Gilson, to augment the continued sale of Richardson slide rules.

Below are my two examples of a Model 812, both marked as “Richardson Rule Works”, but one — the bottom slide rule — also exhibits “Technical Supply Company, Scranton,Pa.” on the slide:

The correspondence schools were likely the main customers for the Richardson slide rules and copies of The Slide Rule Simplified, both prior to and following the Great War and the sale of the business to Gilson, with items distributed by their associated supply companies, which went on for perhaps another one or two decades. In the mean time, Gilson’s company championed on with their circular slide rule endeavors following the acquisition of Richardson’s business.

I have sometimes wondered if George Richardson and Clair Gilson had connected starting in about 1916-17, say, only because this was when the plastic cursors showed up on Richardson’s Pantocrat rules. It is also found that Gilson was advertising in Popular Mechanics as well, starting in 1917. His ad — the earliest I found — for the Midget appears two pages after Richardson’s ad for the Pantocrat system, in the August PM 1917 issue! As Richardson had been advertising for some years, perhaps Gilson was inspired and made contact with him. I agree with other authors that the two men had very similar backgrounds and interests, and could easily have become quick friends.

Gilson’s circular metal rules have plastic cursors, albeit a different design altogether than the Pantocrat rules, but he could have helped to send Richardson down this road. Richardson’s clunky metal cursors covered the scales and made readings difficult at times, while Gilson’s clear plastic cursors were simple and cheap, and made reading the numbers under its hairline much easier with its unobstructed view of the scales. In exchange, Gilson needed to improve his methods for adhering his scales to metal and Richardson had this perfected. So perhaps they had already started talking and giving each other ideas earlier than the time of the sale of the business.

When I first found a Richardson slide rule in Chicagoland about 15 years ago, people seemed still uncertain as to whether or not Gilson had actually acquired Richardson’s business. But in addition to all of the previous circumstantial evidence presented by various authors that Gilson bought the Richardson business, in 2021 a “smoking gun” showed up — an example of a Model 1812 Pantocrat slide rule that is marked both with “Richardson Rule Works” on the body as well as “Gilson Slide Rule Co., Niles, Mich.” on the slide.12 (The Gilson reference is only visible when the slide is pulled out.) This should finally put this particular question to rest.

I’ve also wondered how Richardson could have gotten connected to J. H. Weil & Co. out of Philadelphia to construct the Model 1917 slide rules. One has to wonder if J.J. Clark from Scranton could have been that connection.

There is no mention or use of the phrase “Richardson Rule Works” anywhere in any of the ads or articles I’ve found so far, nor in any of the editions of The Slide Rule Simplified, including the seventh edition, c. 1922. Even the slide rule on the title page of this last known edition shows the words, “Richardson’s Direct Reading Metal Slide Rule” at the top of the rule, rather than “Richardson Rule Works” which was found on the newer Pantocrat rules with the plastic cursors. But, of course, if the text within the later versions book was actually written, copyrighted, and first printed in 1917-18, and simply copied from then on, then this wouldn’t be too surprising.

I’m still waiting for someone, someday, to discover another catalog, instruction manual, or another vintage publication that will provide clarification on the creation of Richardson Rule Works. My best guess is that this name was created in about 1917, likely for legal protection, in relation to his military rule production efforts.

In any event, George Washington Richardson definitely retired at the age of 54, and bought an expensive automobile to tour around in — a Winton Six — as documented in his letter to I.C.S. He continued to live in Chicago, enjoying retirement with his wife, their grown son, and two grandchildren, until he died in 1940 at 75 years old.

And George Washington Richardson’s final address, according to his death notice in the Chicago Tribune, was 4212 West 24^th Place.

• George W. Richardson and J. J. Clark, The Slide Rule Simplified, 7th ed. (Scranton, Pennsylvania: Technical Supply Company, 1918)

• Bruce E. Babcock, “George Washington Richardson’s Direct Reading Slide

  Rules”, Jour. Oughtred Soc. 1.1 p9 (1992)

• Henry Aldinger and Ed Chamberlain, “Gilson Slide Rules — Part I — The Small Rules,” Jour. Oughtred Soc. 9.1 p48 (2000)

• Michael Konshak, “Richardson and Gilson”, Jour. Oughtred Soc. 15.1 p39 (2006)

• John H. Runnels, “The Smoking Gun: The Gilson-Richardson Connection”, Jour. Oughtred Soc. 30.1 p2 (2021)