VI 



explain ;ill that takes place in iiuluslrial j)rocesses, and ou the other hand indusliial 

 processes would be perfected by the application of a complete knowledge of the 

 mechanism of nature. 



Thus, although there is a great dialinction between science and practice, each is to a 

 large extent dependent on the aid of tlie other. Their influence upon each other 

 could be illustrated by the history of any branch of science : it is illustrated by the 

 history of biological arts and sciences. The discovery that the great depths of the 

 ocean were inhabited by living animals was directly due to the laying of the telegraph 

 cable from Europe to America. The medical sciences, anatomy and physiology, sprang 

 not solely from the desire for knowledge, but from the practice of the healing art, 

 and the desire to improve that art. Botany took its rise from the knowledge of 

 simples, the use of plants as remedies for diseases and disorders of the human body. 

 Zoology and comparative anatomy and physiology have been largely aided in their 

 development by the medical sciences. Marine zoology has ever been to a great degree 

 dependent on the assistance of fishermen and fishing engines. Science has received 

 definite additions from investigations carried out with the object of cultivating oysters. 

 The explanation of evolution is sought in the study of the variations of domesticated 

 animals and plants. Are there, on the other hand, any cases in which human arts and 

 industries have directly benefited by the biological sciences ? To answer this question 

 by even briefly enumerating the recent discoveries concerning animal and vegetable 

 parasites which have revolutionised the practice of agriculture would require a 

 volume. But it must be confessed that the fishing industry has hitherto, in tliis 

 country at least, not been greatly benefited by the scientific knowledge of fishes hitherto 

 available. Yet zoological science and the methods of that science have not been 

 entirely without efiect upon tlie supply of aquatic animals for the wants of man. 

 Oyster-culture based upon scientific knowledge has been very successful in Holland 

 and France. Knowledge of the conditions of life of the salmon has been apjjlied to 

 maintain and increase the abundance of that fish in this country, and of allied fishes 

 in America. The shad has been propagated with great success on tlie Atlantic coast 

 of the United States. It remains true that there exists a great deal of scienlific 

 knowledge of marine fishes which has hitherto not at all aflL'cted the sea-fishing 

 industry. But it is also true that no great endeavours have yet been made to 

 bring science and practice in this direction into relation with one another, and also 

 tliat our knowledge of the life of marine fishes is in many respects still extremel}- 



