ON THE UTILITY OF THE NATURAL SCIENCES. 215. 



reptiles, and established the means of distinguishing those which are 

 harmless and useful from those which are poisonous and fatal. 



Naturalists have described about 10,000 species of fishes, a class of 

 animals from which man derives almost incalculable benefits. To be 

 convinced of the truth of this assertion, it is only necessary to glance 

 at the extent and value of the various fisheries in the world. 



About 6,000 species of birds have been described. The value of the 

 study of ornithology has been so beautifully stated by one of the 

 earliest members of the Academy of Natural Sciences, that I will quote 

 his language. Alexander Wilson, in the preface to the fifth volume of 

 his " American Ornithology," says : — 



" In treating of those birds more generally known, I have endea- 

 voured to do impartial justice to their respective characters. Ignorance 

 and stubborn-rooted opinions, even in this country, have rendered some 

 odious that are eminently useful ; and involved the manners of others 

 in fable and mystery, which in themselves are plain and open as day. 

 To remove prejudices, when they oppose themselves to the influence of 

 humanity, is a difficult, and when effected, a most pleasing employment. 

 If, therefore, in divesting this part of the natural history of our country 

 of many of its fables and most forbidding features, and thus enabling our 

 youth to become more intimately acquainted with this charming por- 

 tion of the feathered creation, I should have succeeded in multiplying 

 their virtuous enjoyments, and in rendering them more humane to those 

 little choristers, how gratifying to my heart would be the reflection I 

 For, to me, it appears that, of all inferior creatures, Heaven seems to 

 have intended birds as the most cheerful associates of man ; to soothe 

 and exhilarate him in his labors by their varied melody, of which no 

 other creature but man is capable ; to prevent the increase of those in- 

 ferior hosts of insects that would soon consume the products of his in- 

 dustry ; to glean up the refuse of his fields, ' that nothing may be lost/ 

 and, what is of much more interest, to be to him the most endearing 

 examples of the tenderest connubial love and parental affection." 



Under the- head of mammalogy, naturalists have described about 

 2,000 species of animals, which, while young, subsist on the milk of 

 their mothers. All known quadrupeds, whales, dolphins, &c, are in- 

 cluded in this class. Amongst them are our beasts of burden, the 

 cattle of our fields, and domesticated animals of many kinds. They are 

 familiar to all ; but perhaps everyone is not aware that a full knowledge 

 of their nature contributes to the improvement of agricultural stock 

 and affords indications of rational methods of treating the diseases to 

 which domestic animals are obnoxious. 



Mineralogy teaches the characters- by which simple minerals or stones 

 may be recognised and distinguished from each other." The costly 

 errors into which persons totally ignorant of this science have fallen 

 illustrate its utility. A man in England found upon his farm a 

 great quantity of sulphate of barytes, and, believing from its weight 



