70 OKIGINATION OF LIVING BEINGS. 



mained so for a very long period ; but it is now a con- 

 siderable number of years since a distinguished foreign 

 chemist contrived to fabricate Urea, a substance of a 

 very complex character, which forms one of the waste 

 products of animal structures. And of late years a 

 number of other compounds, such as Butyric Acid, 

 and others, have been added to the list. I need not 

 tell you that chemistry is an enormous distance from 

 the goal I indicate ; all I wish to point out to you is, 

 that it is by no means safe to say that that goal may 

 not be reached one day. It may be that it is impos- 

 sible for us to produce the conditions requisite to the 

 origination of life ; but we must speak modestly about 

 the matter, and recollect that Science has put her foot 

 upon the bottom round of the ladder. Truly he would 

 be a bold man who would venture to predict where she 

 will be fifty years hence. 



There is another inquiry which bears indirectly 

 upon this question, and upon which I must say a few 

 words. You are all of you aware of the phenomena 

 of what is called spontaneous generation. Our fore- 

 fathers, down to the seventeenth century, or there- 

 abouts, all imagined, in perfectly good faith, that cer- 

 tain vegetable and animal forms gave birth, in the 

 process of their decomposition, to insect life. Thus, if 

 you put a piece of meat in the sun, and allowed it to 

 putrefy, they conceived that the grubs which soon be- 

 gan to appear were the result of the action of a power 

 of spontaneous generation which the meat contained. 

 And they could give you receipts for making various 

 animal and vegetable preparations which would pro- 

 duce particular kinds of animals. A very distinguish- 

 ed Italian naturalist, named Redi, took up the ques- 



