124 PROCEEDINGS. 



ierence. When carrying simultaneously through the whole series 

 of discs, the great force required is more than these springs can 

 exert ; and consequently the operation is not completed ; the 

 toothed wheels become in fact locked together. 



It has been pointed out to me by Mr. Joseph Edmondson of 

 Halifax, (England), who is himself the inventor of an excellent 

 calculating machine, that the process employed by Stanhope is 

 precisely that performed mechanically in Babbage's celebrated 

 Difference Engine as well as in that of Scheutz which was founded 

 on Babbage's. He also remarks that in Babbage's Analytical 

 Engine, which was never completed, the carriages are effected 

 simultaneously and " before the additions from which they result." 



Mr. H. C. Russell, f.r.s., one of your Vice-Presidents, who has 

 carefully examined the internal mechanism of Stanhope's Arith- 

 mometer, remarks : — " It is very interesting as indicating the 

 method so painfully slow, by which inventions progress. Mentally 

 of course we add up the shillings until 20 is reached, and then we 

 -carry one, so following this process the Earl arranged his counter 

 to push the next disc on one suddenly. Now it is obvious that 

 there is no necessity for pushing on the second disc in this sudden 

 way. The same purpose would be served by putting on the axis 

 of the shillings wheel a pinion of ten teeth ; and on the second 

 disc a wheel of two hundred teeth, one turn of the shilling wheel 

 would slowly turn the next wheel one-twentieth ; and there would 

 be no need for a stop spring ; and if this method were carried 

 through the whole series of discs there would be no more force 

 necessary to carry one all through than at any other step in the 

 process. But Earl Stanhope was making a machine to do what 

 was before done mentally, and in that way it is more convenient 

 to carry one by a jerk, than to look at it as gradually accruing, 

 and therefore the machine had to carry one by a jerk motion. I 

 want some inventor to go another step and produce a machine 

 which will admit of units, tens or hundreds being added at pleasure. 

 The hundreds by moving the first handle, the tens by the second, 

 and the units by the third. So that the computer reading 765 

 would turn the first handle 7, the second 6, and the third 5, and 

 know that the machine had counted 765, It would be invaluable 

 in meteorological work. I have a design for one, but it has so 

 far gone no farther than the design." 



The following donations were laid upon the table and 



acknowledged : — 



Donations Received during the Month of June, 1890. 



(The Names of the Donors are in Italics.) 



TRANSACTIONS, JOURNALS, EEPOKTS, &c. 



Aberdeen — University. The Aberdeen University Calendar 



for the year 1890 - 1891. The University. 



