424 REVIEWS. 
Dr. Hagen then makes some very just observations on “ the difference 
‘in the aberration of the eyes of the observers. There is no doubt that 
pity that it did not occur to Dr. Hagen to remember what he had written 
essentially excelled those of European make." ‘To my knowledge a di- 
e an w Eu 
‘Thus the American instrument constituted until recently a myth to- 
which all interested in this branch of science gazed with anxious 
curiosity, and prompted me during my two years residence in this coun- 
ry, to become guest x dipasti with it, and I have spared no pains to 
study them carefully.” Here we have distinctly the task set forth, and the 
claim that he spared no pains to accomplish it. Two years of the spare 
time of a busy man was rather short for the imsdestaltng. especially for 
one with an imperfect knowledge of the English rc nt? Let us see 
what were the **pains" taken. “The members of the m icroscopical 
section of the Boston Society «e Natural History, “especially Mr. Bicknell 
so 
coming ** thoroughly acquainted” with the American microscope, for the 
purpose of publication; they were never asked to assist for any such pur- 
pose. Had Dr. Hagen not spared his * pains;” had he enquired i those 
who could have “ assisted” him in his “ study " and have given him “ posi- 
tive proofs," he would have been referred to Professor Holmes and Pro- 
fessor Bacon of his own university, and to Professor Smith of Hobart 
College, New d L have made a study of the micro- 
Scope for twenty years—to Dr. ard, Pres. Columbia College, New 
York; to Professor H. J. Clarke m en Kentucky University; to J. E 
Gavit, Esq., of New Yor k; to Dr. F. W. Lewis of Philadelphia; to Pro- 
disregarded that which he obtained from Messrs. acne and Bicknell. 
