HIS WORKS. ]xix 



lishing what you have amassed with infinite labour, to stir up 

 tempests that may rob you of peace and quiet for the rest of 

 your days." (p. 147.) By and by, however, he produces his 

 Exercises on the Generation of Animals, and though he makes 

 many difficulties at first, urging, among other things, that the 

 work must be held incomplete, as containing nothing on the 

 generation of insects, Ent, nevertheless, prevails in the end, 

 and receives the papers with full authority, either speedily to 

 commit them to the press, or to delay their publication to 

 a future time. Ent set about his office of midwife, as he has 

 it, forthwith, and the following year (1651) saw the birth of 

 the work on Generation. 



Physiological science generally was not sufficiently advanced 

 in Harvey's time to admit of a truly great and enduring work 

 being produced on a subject so abstruse, and involving so 

 many particulars as that of Generation. On the doctrine 

 of the circulation the dawn had long been visible ; Harvey 

 came and the sun arose. On the subject of animal reproduc- 

 tion, all was night and darkness two centuries ago ; and though 

 the light has still been waxing in strength since Harvey wrote, 

 it is only in these times that we have seen it brightening into 

 something like the day. In Harvey's time the very means and 

 instruments that were indispensable to the investigation were 

 not yet known, or were used of powers inadequate to bring 

 the prime facts within the cognizance of the senses. Harvey 

 doubtless did as much as any man living could have accom- 

 plished when he wrote. He announced the general truth : Omne 

 animal ex ovo ; he showed the cicatricula of the egg as the 

 point where the reproductive process begins; he corrected 

 numerous errors into which his master Fabricius had fallen; 

 he further pointed out the path of observation and experiment 

 as the only one that could lead to satisfactory results in the 

 investigation of a subject which gradually displayed itself as 

 one of natural history ; and, it may be added, by his wan- 



