Scientific Lectures. 21 



placed under a microscope, will tell more in one minute to the expe- 

 rienced eye, than could be ascertained by long examination of the 

 mass of disease in the ordinary method." 



To the progress of knowledge in animal and vegetable physiology, 

 the microscope has made invaluable contributions. It has made it 

 possible to detect nature in the very act of those transformations 

 which are concerned in the development and growth of the living 

 organism. It has demonstrated that all forms of organic life, how- 

 ever complicated, originate in the same simple form, the primordial 

 cell, and are built up only by the multiplication and aggregation of 

 cells essentially similar, however apparently differing. It has demon- 

 strated, also, that every complex organism, however it may possess 

 an aggregate individuality, has nevertheless a multiple and complex 

 life, each cell in the aggregate mass being gifted with an independent 

 and distinct life of its own. It has revealed the existence of vast 

 groups of organisms, vegetable and animal, which never attain a 

 higher level than that of the single cell, yet which swarm in all the 

 waters of the earth, and have, in time past, existed in so prodio-ious 

 numbers, that their fossil remains at this time form, to the almost 

 complete exclusion of every other material, the substance of great 

 geological deposits, hundreds of feet in depth, and thousands of square 

 miles in horizontal extent. It has revealed in these organisms a 

 degree of varied beauty and symmetry such as is not surpassed any- 

 where among the more conspicuous of the works of nature. The 

 exquisite patterns sculptured over the surfaces of the silicious shells 

 by which a large class of these minute objects are protected, rival 

 the most ingenious figures executed by the engine lathe. And the 

 elegant forms and graceful movements of others, which seem to be 

 endowed with vital powers of a higher order ; forms and movements 

 Wiiich have no analogies in the world of life with which we are ordi- 

 narily conversant, provide perpetual food for new admiration and 

 new surprise. These things furnish to the observer who comes to 

 the study prepossessed with the idea that the creation, in all its 

 greatest and minutest parts, has been called into being with exclusive 

 reference to the exigencies of the human race, and with no other end 

 but to subserve the uses or to minister to the enjoyments of man, 

 material for profound reflection. And the pride of self-sufficiency 

 with which he has been accustomed to regard himself as the great 

 end of the material universe, cannot fail to receive, from the contem- 

 plation of these marvelously fashioned and wonderfully lovely forms 



