THE ANIMAL KINGDOM. 9 



utmost of his power, and assailed his antagonist sharply, 

 declaring that his discoveries, published for the most part 

 in a low and servile style, were absolutely chimerical. 

 Insult followed hostility, and at last Hartzoeker, resolved 

 to stick at no means and determined at all hazards to pry 

 into the labours of his rival, by the aid of the chief magis- 

 trate of Leyden, introduced himself under a feigned name 

 to Leuwenhoeck, in order to pirate his labours ; but the 

 old microscopist, recognizing him, very speedily showed 

 him the door. 



Leuwenhoeck's woidi really outstrips his means of in- 

 vestigation ; the acute observation of the philosopher tran- 

 scended the power of his instruments, and even now we 

 ask how he can have divined so much and so many things, 

 Avhich they could not have revealed to him. 



In fact, the illustrious Dutchman never possessed an 

 instrument to be compared in point of perfection to those 

 which we use now-a-days ; he only employed simple lenses 

 which he made himself; it was with instruments like these 

 that he made his most important discoveries. Any one 

 can verify this assertion in the museum of the Eoyal Society 

 of London, to which on his death-bed he bequeathed those 

 magnifying glasses that had gained him so much glory. 



Leuwenhoeck's most powerful lenses did not magnify 

 more than sixty diameters, whereas we now possess 

 achromatic microscopes which magnify twelve to fifteen 

 hundred diameters. 



It was recently stated in some of the scientific journals, 

 that two London opticians had succeeded in constructing 

 lenses of 7500 diameters, equal to an enlargement of the 

 surface of 56,000,000 times. It was added that, notwith- 

 standing such an extraordinary result, everything was seen 

 with great clearness. 



