The Arithmometer. 87 



to obtain the fifteen results, consisting in the aggregate 

 of 120 figures, with comfort was 5 J- minutes : 



•12 .. 



78,408 



•52 .. 



418,176 



2-65 .. 



2,149,686 



8-55 .. 



7,736,256 



17-44 . . 



.. 19,131,552 



27-88 .. 



. . 37,348,344 



38-79 .. 



. . 62,693,730 



49-81 .. 



. . 95,239,584 



61-65 .. 



.. 135,521,694 



75-55 .. 



. . 184,886,064 



91-30 .. 



.. 244,541,484 



109-27 .. 



.. 315,938,502 



129-30 .. 



.. 400,423,122 



149-99 .. 



.. 498,426,588 



173-19 . . 



.. 611,588,934 



In order to divide, the dividend must be placed in 

 the result holes, if it be not there already, which is 

 frequently the case, if multiplications or additions have 

 preceded, and the divisor being set on the buttons, and the 

 regulator at division, the slide is placed as far to the right 

 as is possible, consistently with the condition that it shall 

 be possible to subtract the divisor without reducing that 

 portion of the dividend immediately above it, below zero. 

 The handle being turned, the divisor is deducted 

 successively until the figures in the result holes directly 

 above the divisor form a number less than the divisor. 

 The slide is then shifted one step to the left, and the process 

 repeated, and so on until it is not possible to proceed 

 further. The quotient will be found in the quotient holes, 

 and the remainder in the result holes. If we wish to 

 obtain a more extended quotient, we must record and efface 

 the portion already obtained, and transferring the remainder 

 to the left hand end of the slide, proceed as before. We 

 shall thus obtain several additional figures of the quotient, 

 recording and effacing which we may proceed to obtain 

 another batch of numerals, and so on ad infinitum. In 

 this manner the subjoined operation was effected with a 

 machine having six buttons and twelve result discs, in 

 about four minutes : 



987,6 t 7 . S X Jf' B43 = 4-00902656007958725097601 



010,044 



In conclusion, I would state that, like most other things, 

 the arithmometer acts far more efficiently under some 

 circumstances than others, and a very great deal depends 



