88 On the Meteor of April 15th. 



upon the shape in which the computation is presented to 

 it. It frequently needs special formulae and peculiar 

 methods, such as do not at once suggest themselves to the 

 minds of persons inexperienced in its use, and there is 

 scope for the exercise of no small amount of ingenuity, 

 in so arranging the work as to gain the utmost benefit. 

 Some formula are peculiarly suitable for logarithmic work, 

 and rather unsuitable for the arithmometer ; others are of 

 precisely the reverse character ; hence, while I believe the 

 arithmometer to possess great advantages, I do not for one 

 moment anticipate that it will altogether supplant tables of 

 logarithms and reciprocals. Each will be found to have 

 its own sphere of usefulness, within which it has no rival, 

 Moreover, different persons will form different estimates of 

 the value of the machine. Some who through years of 

 incessant practice have obtained a special facility in 

 arithmetical operations will be inclined to regard it as 

 unnecessary ; others, who find arithmetical work to con- 

 stitute a severe tax upon mental energy which could be 

 profitably employed in other directions, will value it 

 highly. ^ 



My own experience is, that I perform my work in less 

 than half the time that I previously required, and with 

 not a tithe of the fatigue. Indeed, I calculate that the 

 saving of time and labour, consequent upon its use during 

 the past two years, has repaid its original cost several times 

 over. 



Art. XX.— On the Meteor of April IHh. 

 By J. Perry, Esq. 



[Read 6th September, 1875.] 



