Calculators/calculating machines

In his inaugural lecture for the chair of theoretical physics at King s College, Coulson noted that the first bill he received at the college was for a calculating machine, and it was made out to the department of "Theatrical Physics." In C. A. Coulson Papers, Bod.Oxford. 

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These are four-parameter equations, and Lola Deming spent weeks at her desk calculating machine to fit the curves that Lambert and Clark obtained for the adsorption of benzene on ferric oxide gel (21). These isotherms are shown in Figure 5. I do not blame anyone for not using these equations, and actually very few have used them to date. Joyner and Emmett (20) were among the hardy souls who did. Clampitt and German published another paper very recently (II), which is well worth reading for all those who deal with Type IV isotherms. 

The application of statistical methods generally in-volves a certain amount of computation. A large part of this is the summing of numbers and of their squares this can easily be performed with a table of squares ( Barlow s Tables of Squares, etc. (E. and F. M. Spon) is a very complete set), and -with a-simple adding machine. For much correlation work on calculating machine (one that will multiply and di-vide) is almost essential. There are a -variety of modds available it can be safely said that the better the machine the more accurately and rapidly can the work be carried out. An electric machine with automatic division and multiplication is really desirable. 

It makes the computation lighter, particularly if we are not using a calculating machine, to use arbitrary zeros and to multiply by 10 or 100, etc., if necessary, to remove the decimal points. Thus in the present instance the variables used are actually —... 

The coming of computers made a quite extraordinary difference to what was possible. When Ian Ross worked on configuration interaction in the MO theory (loc. cit.) he was already experienced and accurate with electro-mechanical calculating machines, and it is not likely that his time of a full day to extract the lowest eigenvalue of a 9 by 9 Cl matrix could have been much bettered. Comparing computational speeds between the early 1950s and the mid 1990s one finds an improvement by a factor of 1012 or more. 

Jeff was a pioneer in the use of computing machines for the calculations needed for structural determinations that would otherwise be repetitious and tedious and take years. For Jeff, calculations in the pre-computer era were additionally frustrating because the mechanical calculating machines available in England worked in pounds, shillings, and pence, back when a pound was worth 20 shilfings and a shilling worth 12 pence. 

In a similar way it was possible to predict10 the carcinogenic activity of a number of molecules in this series when the experimental data were not available. The agreement between the predictions and the experimental results is satisfactory.74. As large electronic calculating machines are now available, it is possible to calculate the charge distribution in molecules17... 

Blaise Pascal (1623-1662). French mathematician and physicist. Pascal s work ranged widely in matiiematics and physics, but his specialty was in the area of hydrodynamics (the study of die motion of fluids). He also invented a calculating machine. 

Blaise Pascal (1623-1662) was bom in France. At age 16, he published a book on geometry, and at 19, he invented a calculating machine. Table 14.2 Multiplicity of the Signal and Relative Intensities of the Peaks in the Signal ... 

The human mind is seldom satisfied, and is certainly never exercising its highest functions, when it is doing the work of a calculating machine. —J. C. Maxwell. 

The calculating machine generates the chain of configurations, again using periodic boundary conditions, subject to the transition probabilities satisfying Eqs. (37) and (38), by moving successively one of tlxe N molecules selected at random, but uniformly, by a random but uniform amount The pressure is obtained by... 

As large electronic calculating machines are now available, it is possible to calculate the charge distribution in molecules ... 

After the war the ENIAC group dispersed in November of 1945 von Neumann was named Director of an Electronic Computer Project at the Institute for Advanced Study, Princeton. The purpose of this project in the words of its Director was to develop and construct a fully automatic, digital, all-purpose electronic calculating machine... which if intelligently used, will completely revolutionize our computing techniques, or to formulate it more broadly, the field of approximation mathematics (/5). Following the ENIAC dedication the next February, Goldstine and Burks joined the IAS Project. Eckert and Mauchly subsequently left the Moore School to establish their own company, the Electronic Control Company, which later became the Eckert Mauchly Computer Corporation and, ultimately, the UNIVAC division of Sperry Rand. 

The second class of problems is concerned with methods for obtaining or at least discussing the solutions of the reactor equations. The coding of these equations for calculating machines belongs to this class. There are, however, more subtle methods among which the transformation of the reactor equations into a variational principle has proved, so far, the most effective. Again, this transformation has been carried out so far only for the most simple problems and it is not known whether all problems of reactor theory can be reformulated as variational problems. 

My own experience with calculating machines is so limited that it would be difficult for me to deal with their use in any detail. This would also be unnecessary, since the use of computers will be discussed by Drs. Ehrlich, Varga, Richtmyer and Carlson along with the mathematical models, such as multigroup theories, which the availability of computers inspired. 

Babbage, Charles (1792-1871) British mathematician who is best known for his early work on mechanical calculating machines. He began work on his first difference engine in 1823, but abandoned it ten years later due to lack of funds. His second machine of 1834 was a programmable punched-card analytical engine , but this too was never completed. 

Pascal, Blaise (1623-62) French mathematician and physicist. An infant prodigy, he had aheady made a mechanical calculating machine by 1642. in physics he formulated Pascal s law concerning fluid pressure and the principle behind the hydraulic press. The Si unit of pressure is named after him. 

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