274 MEMORANDA. 



would be attended with difficulties, perhaps, at least for a 

 time ; and if they were sold at prices proportionate to those 

 now charged for the ^th and ^th, it is probable there 

 would be but few purchasers. It is these considerations, I 

 believe, and not the uselessness of higher powers, that make 

 our opticians say nothing is to be gained by increasing the 

 power of the object-glass. 



Mr. Wenham will, I hope, consider it his high privilege 

 to show, not only that higher powers are useful, but that 

 they may be sold at moderate, yet remunerative, prices. No 

 one is more ready than I to admit that the labourer is 

 worthy of his hire, but if we are to have (as I hope we shall 

 have) glasses of much higher power than those now made, 

 and are to take the denominator of the fraction* expressing 

 their focal length as the number of pounds sterling of their 

 price, it is certain few will be willing, even if able, to incur 

 so large an outlay upon a single object-glass. — J. Mitchell, 

 Lieutenant, Madras Army. 



* Powell's l-16th costs £16. At this rate, a 1-SOth, of course, would 

 be £50, a price that would place it beyond the reach of any but the most 

 wealthy. There is something that I, at this distance, cannot understand in 

 the difference of prices by different makers. Powell and Lealand charge 

 10 guineas for a l-12th, and Ross £18. But no one will say that one 

 glass performs better than the other — a bit of information, by the way, 

 that would be useful to people in the colonies. 



