CHAPTER ELEVEN

Fruits of the Conflict: Machinery 1922

THE ARMISTICE LEFT the United States with a vast pool of equipment, energy, and vision. Beginning in the winter of 1919, train after train arrived at the Aberdeen Proving Ground with field artillery pieces that had been built for a final offensive into Germany. The proving ground staff unloaded the weapons, one by one, and towed them to the large fields where Oswald Veblen had conducted his first range tests. They placed the guns in long, straight lines to await the next war to end all wars. As the army was starting a period of slow decline, they sat in winter snows and summer heat, leaving the base only when some veterans’ lodge requested a gun to use as a lawn decoration or to serve as a memorial to fallen comrades.

The trains carried surplus punched card tabulators and sorters and punches north from the government office buildings to the warehouses of the Computing, Tabulating and Recording Company in New York. “Rising inventories became a problem in 1919 and 1920,” wrote historian James Cortada, “before commercial enterprises could sift production back to civilian levels.”¹ Unlike the field artillery in storage at Aberdeen, some of this equipment would form the basis for a new class of scientific computing laboratory, a type of laboratory that would combine the tabulators with the expertise of human computers. Two veterans of the Food Administration would shape this new kind of computing facility, Henry A. Wallace and Howard Tolley (1889–1958).

Howard Tolley was one of the last links to Myrrick Doolittle and, through him, to Benjamin Peirce. He had come to Washington in 1910 and become a computer for the Coast and Geodetic Survey office. “[The job] consisted of sitting in an office up … on Capitol Hill and running a computing machine,” he later wrote, “computing such things as the latitude and longitude of particular triangulation stations in different parts of the United States and computing the altitude of different hilltops and mountaintops.”² Doolittle was only a few years from retirement, but he was still a guiding force in the office and taught the new computers his method of computing least squares adjustments to surveys. Tolley was initially intrigued with this work, thinking that it was “the only part that required any knowledge of real mathematics,” but before long he recognized that the calculations “follow[ed] a regular fixed routine, requiring no judgement.”³ After a few months of adjusting surveys, Tolley tired of the work. “What is there to this?” he complained. “I [would] come over to the office every morning at nine o’clock and I [would] work on computing these things, adding, multiplying, running these computing machines, deciphering what’s in the books of these surveyors.” The job paid $100 a month, a sum that had been unchanged for nearly twenty-five years. “In effect it’s all spent before I draw it, and I [had] a pretty hard time keeping good clothes on my back.”⁴

24. Howard Tolley (back row right) and Henry A. Wallace (front row center) at U.S. Department of Agriculture

Tolley’s frustration was compounded by the knowledge that the major surveys of the North American continent were complete and that he was only handling refinements and detailed adjustments. “Just being a computer in the Coast and Geodetic Survey was completely futile,” he later remembered; “it wasn’t helping the world any.” He considered returning to college for graduate study or even joining a survey team for the Alaska railroad, but he concluded that graduate study was expensive and that the surveyors “didn’t want a desk mathematician.”⁵ One morning, when Tolley was chatting with his supervisor in the Coast and Geodetic Survey offices, he learned that the Department of Agriculture was seeking a general-purpose mathematician to work on some “problems that were related to genetics—Mendelianism,—and on some that were related to the capacity of farm silos.”⁶ When he went to interview for the job, Tolley discovered that the Department of Agriculture was most interested in what he had learned from Doolittle, the “knowledge of least squares and the adjustment of observations.”⁷ He accepted a position with the department and worked on a number of issues that were fundamentally economic in nature. During the war, he assisted Raymond Pearl with the statistical work of the Food Administration and, in 1921, became one of the first members of the department’s new Bureau of Agricultural Economics.⁸

In January 1921, the United States inaugurated a new president, Warren G. Harding, and the Department of Agriculture welcomed a new secretary, Harry C. Wallace. One of Wallace’s first acts was to create a new research office called the Bureau of Agricultural Economics. This office collected together all the employees of the department, including Howard Tolley, who were engaged in studying problems of production, markets, and financing. Within this group, Tolley promoted the method of least squares as a means of analyzing agricultural data. This application of least squares was substantially different from its use in survey adjustment, even though the method of calculation was unchanged. In agricultural studies, least squares did not adjust data. Instead, it took data apart in order to identify underlying causes or forces. It could identify the effect of fertilizer on crops or the feed that increased the weight of farm animals. It was sometimes called “regression analysis” or “the analysis of variance.”

In the fall of 1922, Tolley gave a series of lectures in order to introduce the staff of the Bureau of Agricultural Economics to the ideas of statistical least squares.⁹ Tolley illustrated the theory with an example that concerned the damage done to cotton crops by the boll weevil. His data, gathered in the southern states by agents of the department, contained the extent of damage on each field, the typical size of the cotton plants, the time of year, the amount of rain recorded in the area, and the daytime temperature. Using least squares analysis, Tolley showed how it was possible to determine which of these factors were present in the most heavily damaged fields. According to his results, the plants were most vulnerable at a certain stage of their development.¹⁰

Though the method of least squares promised much to the agricultural researchers, it was of little use unless the department could provide a computing office. The calculations were every bit as daunting as the least squares calculations of survey adjustment. A survey calculation would be done only once. A least squares analysis of a specific problem might have to be repeated every season. Tolley believed that at least some of the calculations might be handled with punched card equipment. In agricultural statistics, as in survey adjustment, least squares computations had two distinctly different parts. The first part reduced the data to a series of normal equations. By itself, this activity was especially demanding for agricultural researchers, as they were often dealing with large collections of data that spanned counties or states or regions. The punched card equipment of 1922 could summarize data for many applications, but it needed to be used in a special way for least squares calculations. The normal equations required multiplications, and punched card tabulators could only compute sums. There was a simple way to force the machine to perform multiplications, but it required a skilled and attentive operator. The method, called progressive digiting, reduced multiplication to primitive additions. A simple product, such as 24 × 127, would require six cards. Four cards would have the number 127 punched on them. The other two would have the number 1270. To compute the product, the tabulator would sum the six cards.

When applied to real problems, progressive digiting seemed to be an awkward process, a complicated operation that should have been straightforward. It was something akin to counting the number of sheep in a field by summing the number of legs, adding the number of ears, and dividing the result by six. To handle real problems, operators had to punch multiple cards, sort them, sum them in a tabulator, shift the values, and sum again. It was difficult work, but it was faster and more accurate than the alternative of doing the computations by hand. For large collections of data, those that had been gathered from one thousand or two thousand farms, the punched card equipment provided the only practical way of preparing the normal equations.

Punched card technology offered no help with the second step of least squares analysis, the step of processing the normal equations. The only way to do it was to give the numbers from the tabulating equipment to a staff of human computers and let them complete the work. They would use a mechanical calculating machine and the mathematical method invented by Myrrick Doolittle some forty years before.¹¹ Even with Doolittle’s method, this part could be time-consuming. Tolley advised researchers to minimize the labor by doing all calculations with only two digits after the decimal point. He defended this procedure by noting that agricultural research was imprecise and that “astronomical accuracy is really not necessary.”¹²

After teaching his class on least squares analysis, Howard Tolley moved to create a central computing laboratory for the Bureau of Agricultural Economics, an office that had punched card equipment and the expertise to perform least squares calculations.¹³ In 1922, three separate offices of the bureau had punched card equipment, but none of them was fully utilizing its equipment. “The installation of the Cost of Marketing Division is busy most of the time,” he reported, but “that in the Division of Land Economics about half the time, and that in the Division of Statistical and Historical Research something like one-third of the time.” His research suggested that none of these computing offices really understood how to prepare a problem for machine tabulation and that at least one office had started problems that it had been unable to complete.¹⁴

25. Computing room at the U.S. Department of Agriculture

In the winter of 1923, Tolley received the approval of the department’s senior statisticians to create his centralized office. Even with this approval, the task was challenging, as none of three offices was prepared to surrender its punched card equipment. The possession of an expensive piece of machinery was a sign of power and importance, even if the machine was not well used. Tolley worked with each of the offices, arguing that a centralized tabulating facility could “rearrange schedules and adjust them to cards in such a way that both the cost of tabulation and the elapsed time between the collection of data and the completion of tabulation would be materially reduced.” By April, he had convinced all three offices that they would benefit from a central computing division.¹⁵

For the new computing laboratory, Tolley had to choose between competing brands of equipment. Two of the offices leased their equipment from the CTR company, which was in the process of changing its name to International Business Machines. The third office used the tabulators of the Powers Accounting Machine Company. Powers had been founded by a former census employee. His machines could tabulate the International Business Machines cards, but they operated in a slightly different manner.¹⁶ Tolley chose to keep a unified shop and leased only International Business Machines equipment. He completed the work by the first of May and announced that the “tabulating and computing services will be available to all” engaged in economics research.¹⁷

When the office began operations, it was able to handle only the first part of the least squares computations, even though it employed thirty workers. The staff of this office were called “operatives,” not computers. For most calculations, they punched cards and ran tabulators, following instructions that had been prepared by researchers in the Department of Agriculture.¹⁸ The office was led by a statistician who provided advice to the various divisions of the department. He showed others how to organize their data and prepare it for punching, but he did nothing with advanced mathematics. The second step of least squares calculations was left to the bureau researchers and their assistants.¹⁹

A second computing laboratory was created with the assistance of the younger Wallace, Henry A., at Iowa State College in Ames. Henry A. Wallace did not move to Washington with his father but remained in Iowa to edit the family newspaper. From this position, he continued his statistical research. With the help of friends and subscribers, he would gather data from all over the state of Iowa, punch it onto cards, and summarize it with the tabulators of a Des Moines insurance company.²⁰ He used the results to recommend farming strategies to his readers. During the early 1920s, he urged Iowa farmers to change their mix of crops, a campaign he summarized as “More Clover, Less Corn, More Money.” Though he generally used only simple numbers to support his ideas, Wallace could not resist the temptation to demonstrate his mathematical sophistication. By 1922, he was conducting least squares analyses of agricultural data and publishing the results in Wallace’s Practical Farmer. At the end of one article, he proclaimed, “For the benefit of our statistical friends, we may say that our predicting formula has a multiple correlation coefficient of .91, which indicates a very real degree of accuracy.”²¹ Of course, few of his statistical friends read Iowa farming papers, and few of the hog farmers understood the mathematics of multiple correlation.

With his father running the Department of Agriculture, Henry A. Wallace had the opportunity to meet Howard Tolley and followed the development of the new computing facility at the department.²² In the winter of 1923, Wallace followed Tolley’s example and taught his own class on the subject of least squares. His classroom was at his alma mater, Iowa State College. The students were college researchers, senior faculty, and a graduate student or two. Some already knew the basics of least squares. One had served on the Food Administration as one of the “expert swine men.”²³ In ten Saturday sessions, Wallace developed the fundamental theory of least squares, demonstrated how to prepare the basic equations, and showed how Doolittle’s method could be used to compute the final answers. For most of the classes, he had a desk calculator on hand, a “cheap key-driven machine,” he later recalled. For the last class, he decided to show how to compute correlations with a punched card tabulator. He borrowed a punched card tabulator in Des Moines, loaded it into the back of a truck from the family farm, and drove north to the Iowa State campus. He spent the morning explaining how the machine worked and demonstrating statistical calculations with it.²⁴

Assisting Wallace in the classroom was an Iowa State College mathematics professor named George Snedecor (1881–1974). Snedecor held a master’s degree in physics and had been hired in 1913 as part of an effort to improve the university’s science and engineering departments. After his arrival at the campus, he had quickly recognized that the school had a greater need for a statistician. He had no connection to Karl Pearson, who was recognized as the founder of mathematical statistics, but he had studied some statistical methodology in college and was able to teach courses in elementary methods. He spent much of his time compiling the methods of statistical practice in a form that could be used by researchers in any discipline, though his examples tended to favor the agricultural research that dominated the campus.²⁵

In 1924, Snedecor and Wallace wrote a pamphlet entitled Correlation and Machine Calculation, a paper that would have fit nicely into Karl Pearson’s Tracts for Computers. It dealt with “practical difficulties” of using least squares techniques for computing correlation problems. The pamphlet showed how Pearson’s correlation analysis was actually a form of least squares work and then described how Doolittle’s method could be used to do the calculations. The two authors made only a passing reference to punched card technology, but they noted that “where the number of observations runs into the thousands, punched cards should be used with sorting and tabulating machines.” The “machine calculation” promised in the title was the calculation done by a human computer with a “commercial form of adding machines.”²⁶

While he worked on the pamphlet, Snedecor experimented with punched card calculation. He leased a card punch, which he kept in his university office. This was a small device, little bigger than a standard dictionary, and consisted of a wooden base, a frame for the card, and a sliding pad with keys numbered from 0 to 9. He punched each number one digit at a time, advancing the slide as he progressed. Any mistake would ruin the card so that he would have to start afresh. Once he had punched a set of cards, he would send them to Des Moines to have them tabulated.²⁷ As he gained skill with punched card machinery and began to appreciate what he could do with it, he began to drift away from Wallace. There was no conflict or disagreement between the two, just diverging interests. Snedecor was devoted to statistical research and to the support of scientific study. Wallace was interested in many things and was devoting more time to political causes and new business ventures. His political goals were embodied in a congressional bill that would open new markets for farmers. His new business was a company that produced and marketed hybrid corn seed.²⁸

Snedecor’s experiments with punched card machinery slowly grew into an organized computing laboratory. He did not have the kind of resources that could be found at the Department of Agriculture in Washington but he was able to hire a human computer in 1925 and acquired a punched card tabulator two years later. When the machines arrived, he discovered that his office did not have the proper electrical wiring for the tabulator, a minor setback that forced him to find a room in another building for his laboratory.²⁹ Once he had the equipment operating, Snedecor was temporarily overcome with the fascination of new love, the kind of fascination that researchers before and since have bestowed upon new machines. Snedecor demonstrated punched card techniques to any interested researcher and used the tabulators to solve dozens of problems, including many that had no relationship to statistics and a few that were not particularly suited to punched cards. He summarized field trials, factored numbers, built databases, and solved differential equations.³⁰ His dean grew tired of his lengthy descriptions of punched card computations and suggested that, in the future, Snedecor might simply summarize his accomplishments.³¹

Snedecor named his laboratory the “Mathematical and Statistical Service,” a title that defined the role of the office within the college and suggested that Snedecor’s machines might be leased by outside clients. It was not the only university computing office in the country. The International Business Machines company was attempting to place its products at colleges and universities. In 1927, the year that Iowa State College acquired its machines, International Business Machines leased tabulators to at least four other schools: Cornell University, Columbia University, the University of Michigan, and the University of Tennessee.³² Unlike the other sites, the Iowa State facility combined tabulating machines and human computers. The machines summarized data and computed the basic values for least squares problems, just like the machines at the Department of Agriculture in Washington. The computers completed the work, solving the problems by using Snedecor’s and Wallace’s variation of Doolittle’s method.

26. Iowa State Statistical Computing Service

One computer, Mary Clem (1905–1979), rose to play a central role in Snedecor’s laboratory. Clem came from western Iowa and had only a high school education. Mathematics, she later claimed, “was my poorest subject,” a boring topic that never interested her. By contrast, she thought that computing was something entirely different. “The more I worked with Snedecor,” she said, “the more fascinated I became with figures and data. I got to the point where that was my whole life.” She became especially good at identifying patterns that could be used for detecting errors, values that she called “zero checks.” A zero check was a sum that should equal zero if all the numbers had been correctly calculated. Such sums often escaped the eyes of those with more mathematical training. The first time that she presented one of these checks to Snedecor, he was skeptical. Clem recalled that “he sat there thinking about it a little bit, and he turned around and went through algebraic fiddling around and he said ‘that’s right they do.’ ”³³

Because of her insight into calculation, Clem became the planner for the laboratory, a worker occupying a middle level between the human computers and the research scientists. She was remembered as a strong presence in the lab, a leader who set the schedule, trained new computers, and enforced discipline.³⁴ She oversaw about six computers and one machine operator. Many of these computers were graduate students or the spouses of graduate students. A few were local high school graduates like herself. The majority were women. Clem felt that men never adapted to the work, judging that “they would rather probably teach or do research work.” Male or female, most of her computers were transients, working for only “two or three years” before they left the lab.³⁵

Even with the combination of card tabulators and human computers, Clem and Snedecor found that there were problems that were too demanding or too expensive for the lab to undertake. One such problem was presented to the lab by Henry A. Wallace. In 1930, Henry A. Wallace conceived the idea of looking at long-term weather records and comparing them to astronomical ephemerides. He reasoned that the weather was a complex system driven by outside forces. He acknowledged that the radiation of the sun and the gravity of the moon were the largest of these forces, but he speculated that the planets might also exert a physical force upon the weather. Undeterred by what others might think of his plan, Wallace began to develop a framework in which he might search for a relation between the positions of the major planets and the weather on Earth.

Karl Pearson and Frances Cave-Browne-Cave had used correlation analysis to search for connections between weather patterns on the Atlantic Ocean. Wallace borrowed their methodology in order to connect fifty years of climate data with planetary data from nautical almanacs. He began with the ephemerides, punching one card for each of the 18,261 days in the fifty-year period of his study. Each card contained a code for the date, the positions of the moon and the major planets, and a blank spot for weather data, such as the daily rainfall in Des Moines, the high temperature in Cedar Rapids, or perhaps the wind direction in Ames.

Wallace had become a prominent political figure, though he had not quite reached the national stage. When his political opponents learned of his weather research, they mocked it as “weather astrology,” a form of research that properly belonged in the misguided world of Jonathan Swift’s Laputa.³⁶ The study was probably naively conceived and certainly belonged to a branch of meteorology that contributed little to the understanding of the weather, but its scientific validity is less important than the scale of the research. To compute a single correlation statistic, Wallace would have to duplicate his set of cards, punch his weather data on each of the 18,261 cards, compute the basic statistics for the correlation, and give those statistics to a human computer to finish the calculation. In this process, the final step was insignificant. The few multiplications and the single division needed to compute the correlation were dwarfed by the other activities. With machines of the 1930 era, a skilled operator would take three hours to create a duplicate set of cards, forty working days to punch the weather data onto the duplicates, and then twenty-one days to compute the basic parts of the correlation. The human computer would need a mere fifteen minutes to complete the task.

Wallace attempted to entice the Iowa State Mathematical and Statistical Service to continue the research. “This study seems to be of such unusual fundamental value that I cannot help but feel if would be a splendid thing if you people at Ames could take over these cards,” he wrote to George Snedecor. Busy with his new hybrid seed company, Wallace offered to donate his 18,261 cards to Iowa, suggesting that the database was of “unusual value.”³⁷ Snedecor declined the offer, perhaps sensing that the project was not founded on a firm understanding of meteorology and certainly knowing that such a demanding project would have easily overwhelmed his modest staff and his relatively simple punched card office. His computing laboratory ranked among the most powerful scientific computing facilities of the age, even though it consisted of no more than seven or eight people: Mary Clem, a small staff of computers, and an operator for the tabulator. They could process far more numbers than Pearson’s Galton Laboratory with its collection of Brunsviga calculators. Wallace’s weather calculations, even if they were based upon valid science, would have consumed all of their time and effort.

The computers at the American Telephone and Telegraph company were veterans of the First World War in the sense that the computing division of the company began to take shape during the summer of 1918. The company had expanded at the start of the war in order to provide the army and navy with radios and telephone equipment. It had a long history of scientific research that could be traced back to the original telephone of Alexander Graham Bell (1847–1921) in the 1870s. Company scientists studied a variety of problems that were related to telephone services. Chemists studied new materials for insulating wires; physicists looked at the propagation of radio waves; and statisticians evaluated different designs for operator stations. The computing division was an offspring of the transmission section, the group that was working to develop reliable and efficient long-distance telephone lines.³⁸

The calculations of telephone transmission imposed special demands because they utilized a form of arithmetic that involved complex numbers. Each complex number consists of two values. For historical reasons, one value is call the “real part” and the other is called the “imaginary part.” Because of these two parts, complex arithmetic requires more labor than ordinary arithmetic. The sum of two complex numbers requires two ordinary additions. A complex multiplication requires seven ordinary operations: four multiplications and three additions. The most taxing operation, complex division, requires sixteen steps: eight ordinary multiplications, six ordinary additions, and two ordinary divisions.

Though complex numbers increase the amount of calculation, they actually simplify the analysis of electrical circuits, particularly the analysis of vacuum tubes. The vacuum tube amplifier had proven to be the key technology for long-distance transmission. American Telephone and Telegraph had built a prototype amplifier in 1912 and had demonstrated a transcontinental circuit at the 1915 San Francisco World’s Fair.³⁹ In 1916, the company hired a mathematician, Thorton Fry (1892–1991), to assist the electrical engineers with their analyses. In the first year of the war, Fry hired a computer, Clara Froelich (b. 1892). Froelich was a graduate of Barnard College, the women’s school affiliated with Columbia University. From what we know about her early years, Froelich was a reserved woman, a student of mathematics who had complained about being isolated among the social circles of Barnard.⁴⁰ She shared the computing duties with two other computers, but she proved to be the only permanent member of the computing staff. Fry preferred to hire recent graduates of women’s colleges, and few of these workers stayed at American Telephone and Telegraph for more than a year or two.

27. Thornton Fry and computer at American Telephone and Telegraph

In 1922, Fry, Froelich, and the other computers were removed from the long-distance transmission division and given their own office, the division of mathematics.⁴¹ Their office occupied one corner of a yellow brick building that sat on the Manhattan riverfront about two miles north of the New York headquarters of American Telephone and Telegraph. As was common in office buildings of the day, no partitions divided each floor to separate the work spaces. The computers could watch the staff of electrical engineers studying the behavior of a vacuum tube or the properties of cables. They could smell creosote drifting up from the laboratories responsible for preserving the wood of telephone poles. From their desks, the computers could look south toward the skyscrapers of Wall Street or watch ships struggling up the Hudson River to the west. In 1925, the building, the computers, and the rest of the researchers were transferred to a new organization, named Bell Telephone Laboratories. Bell Laboratories was the largest of the many industrial research facilities formed in the 1920s. By the end of the decade, “more than 1,600 companies reported that they supported research laboratories,” wrote historian Robert Reich, “employing nearly 33,000 people in all.”⁴²

The mathematics division of Bell Telephone Laboratories “does not regularly supply computing services to other departments,” wrote Fry in 1925. He explained that computation was usually “performed by special groups of calculators in the departments where their services are required.”⁴³ Froelich and her peers worked with Fry to develop new methods for calculation, advised other researchers on computational issues, and helped instruct the computers of other departments. Like many scientists of the age, Froelich studied the operation of IBM tabulating equipment, hoping that it might be adapted to the calculations of the company’s engineers. The mathematics division did not have its own machines, so she was required to spend evenings in the company’s accounting office with the tabulators that were employed for business transactions by day. She “made valiant efforts to use [punched card tabulators] for more purely mathematical problems,” reported Fry, “but with little success.”⁴⁴

Froelich had greater success with the new desk calculating machines. These machines were the direct descendants of the geared adding machines of the 1890s. In the intervening years, they had acquired electric motors and a fuller set of operations. By 1925, the computing staff could claim to be experts on two machines, one called the Millionaire calculator and the other the Mercedes. The Millionaire had a mechanical multiplication table, while the Mercedes could “perform automatic division, requiring only that the operator set up the divisor and the dividend in proper registers, but not requiring any further supervision.” All of these, she found, could be used for the two-part operations of complex arithmetic.⁴⁵

The individual who acquired a reputation for adapting commercial business calculations “with little or no change in construction—to scientific computing” was L. J. Comrie.⁴⁶ Though Comrie was intrigued with the idea of building special-purpose machines for scientific problems, he argued that there were many benefits to be gained from commercial machines. First, they were generally flexible. Second, they were usually quite reliable, the product “of groups of experts,” rather than a “single and perhaps not too experienced designer.” Finally, he argued that they were “economical as compared with the overhead costs of design and construction on a small scale.”⁴⁷

After leaving Karl Pearson and the Galton Laboratory, Comrie had moved to Cambridge and had studied astronomy. Slightly older than most students and calloused by his brief experience at the front, he did not easily fit into the society of graduate students. Rather than focusing on the narrow subjects of astronomical theory and the automatic collection of data, he looked to the larger astronomical community and attempted to make a mark. Before completing his doctorate, he had organized a computing section for the British Astronomical Association, a loose network of twenty-four volunteer computers that prepared special tables for the association.⁴⁸

During the early 1920s, Comrie emerged as a restless and ambitious individual. Little in the scientific world met his standards. The computers at the Greenwich Observatory were the first to feel the lash of his criticism. After spending two months in the observatory computing office, Comrie concluded that the computers used inferior methods in their work. Believing that the observatory staff were not listening to his remarks, he made his complaints publicly.⁴⁹ In the years that followed, he was often sharp and occasionally angry. While teaching at Swathmore College in the United States, he complained about his teaching duties. When he moved to Northwestern University in Illinois, a school that seemed to be more open to him, Comrie felt that he was unappreciated and underpaid. “I feel that my qualifications and experience entitle me to a better position than the one that I now hold,” he wrote to the university president.⁵⁰ He found satisfaction only in calculation and looked for a time when he might return to London and take charge of the most sophisticated computing office in England, the computing floor of the Nautical Almanac. In 1925, anticipating that the almanac director would soon retire, the British Admiralty offered him a position in the almanac office.⁵¹

At the almanac office, Comrie experimented with punched card tabulators. His initial experiments, though promising, were not as important to him as a test of a new accounting machine. This device, called the National Accounting Machine, had multiple registers, sets of gears that would store several numbers. These registers were used to keep different sums for accounts. A single action might post a number to the general ledger and accounts receivable. In these multiple registers, Comrie saw a machine that could be operated as a difference engine. It can “be called a modern Babbage machine,” he wrote, for “it does all that Babbage intended his difference engine to do and more.”⁵² For a century, Babbage’s difference engine had been a distant but desirable goal, a machine that promised to simplify many almanac computations. Babbage, of course, had failed to complete such a machine. The difference engine built by George and Edvard Scheutz had been sensitive, prone to failure. In a moment, Comrie had discovered a difference engine that was robust, was mass produced, and had “spare parts and expert service … readily available.” “Above all,” wrote Comrie, “others interested may purchase the machines at a moment’s notice and at prices that are economical.”⁵³

The economics of the National Accounting Machine was important to Comrie, as the British Nautical Almanac Office had little money for computing machinery and no funds for developing new computing devices. He would recall the almanac office as a place of “politics and red tape,” but this judgment was colored by his later experiences.⁵⁴ During the 1920s, he was able to find enough funds to outfit the computing room with ordinary mechanical calculators for production work and was able to purchase a National Accounting Machine with money he acquired from the Mathematical Tables Committee of the British Association for the Advancement of Science. The British Association had been founded in the 1830s by Charles Babbage and his friends as an alternative to the Royal Society. The Mathematical Tables Committee had been formed in 1871, the year of Babbage’s death. It consisted of a small group of mathematicians, numbering between six and twenty, who prepared mathematical tables. Since its founding, it had published about fifty tables in the reports of the British Association for the Advancement of Science.⁵⁵

In 1925, the Mathematical Tables Committee was the only professional organization for human computers. It was dominated by the colleagues of Karl Pearson and the students of Pearson’s Galton Laboratory.⁵⁶ The committee invited L. J. Comrie to join their group in 1928, and Comrie eagerly accepted the appointment. He was “a persistent self-publicist,” wrote historian Mary Croarken, and “saw the [Mathematical Tables Committee] as a means to improve his standing in the wider scientific community.”⁵⁷ Within a year, Comrie had established himself as the leader of the group, even though he officially served the committee as its secretary rather than as its chair. He arranged for the Mathematical Tables Committee to have space in the offices of the Royal Astronomical Society, established a regular schedule of meetings, and outlined an ambitious computing program for the group. Under his urging, the committee agreed to prepare and publish volumes of tables.⁵⁸

The Mathematical Tables Committee had few resources to support its work, but it had two small legacies, which had been left to the committee by former members. The constraints on these legacies specified that the money should be used to compute certain kinds of tables. Comrie was not especially interested in those tables and chose to interpret the legacy requirements liberally. He used the money to purchase a National Accounting Machine and two Brunsviga calculators, reasoning that these machines could be used to prepare the specified tables. Once the legacy tables were complete, he turned to other problems that he thought more worthwhile.⁵⁹ He kept the new machines at the offices of the Nautical Almanac, even though they were not the property of the British government. In itself, this decision was unremarkable, as the almanac staff included some of the most skilled computers in the country, and Comrie was an acknowledged expert on computing machines. Yet, in combining the resources of the two organizations, he did not always differentiate where the production of the Nautical Almanac ended and the work for the Mathematical Tables Committee began. Sometimes the National Accounting Machine prepared tables for the almanac. At other times, the almanac computers helped Comrie prepare tables for the Mathematical Tables Committee. On at least one occasion, the group did some calculations for Karl Pearson, who was affiliated with neither organization.⁶⁰

By 1930, L. J. Comrie had climbed the central pillar of British scientific calculation and taken his place as the country’s senior computer, the superintendent of the British Nautical Almanac. He directed a staff of about a dozen that used Brunsviga calculators and the National Accounting Machine. His elevation occurred as he was completing a first book of tables for the Mathematical Tables Committee, “a most admirable volume,” in the opinion of one reviewer, “which ought to be in every college mathematical library.”⁶¹ Like Howard Tolley and Henry A. Wallace, he foresaw a grand future for computing, but the contemporary English landscape was less impressive. Outside of the Nautical Almanac Office could be found the London stock market, whose members had fallen into hard times as the price of corporate shares had fallen At the edge of the city there were factories, gates closed and windows shuttered. Men and women walked the streets looking for a job, a handout, a scrap of food. When the winds blew from the east, one could catch from across the channel the faint smell of mustard gas, the lingering scent of the old battles.