36 MEMOIR OF ALFRED SMEE. [Chap. IV. 



and again every other ten days, till December 31st, 1861. How many 

 aphides in all, if the mother aphis and her whole progeny were alive on the 

 31st of December ? 



Every aphis weighed -^ grain. What was the total weight of the aphides 

 so produced P — Alfeed Smee. 



Answer. 

 Let a = total number of generations from the mother aphis = 36. 

 Let h = the number at each birth = 10. 



The formula will be 1 + ab + (a - 1) V + (a - 2) 6' + etc 



(a - 35) 6'». 



The answer to the first question, i.e. what number of aphides in all, 

 is — 

 1,234,567,901,234,567,901,234,567,901,234,567,861 aphides, or nearly 

 li sextillions of aphides. 



The answer to the second question is — 

 78,728,820,231,496,422,293,148,463 tons weight, or nearly 78f quad- 

 rillions of tons weight. 



Besides interesting himself with aphides, we find him occu- 

 pied on other subjects ; for in 1846, in conjunction with one of 

 the managers, he was engaged on the ventilation of the theatre 

 of the London Institution. To draw comparisons is odious : yet we 

 cannot hut wish that all public rooms were as well ventilated as 

 is the theatre of the London Institution. During different periods 

 of his life he was employed on the ventilation of various large 

 buildings, and the Grand Hotel at Brighton owed its proper 

 ventilation to him. 



During 1846 he was invited to take part in a discussion at 

 the Civil Engineers' on the explosion of boilers, as he was known 

 to have turned his attention to the subject. 



In 1847 he invented an ether-inhaler, which was exhibited 

 at his soiree. The first one was made by Messrs. Maw, of 

 Aldersgate Street. The ' Illustrated London News ' * says — 



In a former number (245) we called attention to the important medical 

 discovery, whereby a state of the body could be produced by the inhalation 

 of ether, which renders the patient insensible to the pain of the most 

 severe operations. Since the discovery has been promulgated, medical 

 men have been actively engaged throughout the country in prosecuting 

 their inquiries upon the subject, and numerous forms of apparatus have 

 been devised for conducting the inhalation. 



It is found by experience that the more rapidly the effect is produced 



January 30th, 1847. 



