HI|TORY OF NATURE IN THE AFFAIRS OF LIFE. 51 



such of the^- subjects as are known, at present, to be connected 

 with human pursuits, but with the abstract philosophical history 

 of nature, which, at first sight, may appear unconnected with 

 obvious utility. Another fact concerned also supports this latter 

 inference : Mr. Macleay's pursuits are those of the philoso- 

 phical naturalist ; he is engaged in the purely scientific culti- 

 vation of Zoology in general, and of Entomology in particular, 

 merely as branches of science, and without any direct view to 

 their utility in the affairs of life ; and yet, when the applica- 

 tion of such knowledge was necessary, he pointed out, from 

 this abstract science, the proper and effectual means of pre- 

 serving forests from these destructive insects. 



I am now to offer some observations on the value of uniting 

 a knowledge of the Physical with that of the Mathematical 

 sciences. The utility of the latter is so well appreciated, 

 their applications in commerce and in the arts, and the ten- 

 dency of their higher branches to invigorate the reasoning fa- 

 culties, together with their immense and indispensable use in 

 Astronomy, are so well understood, and so extensively acted 

 upon, in Education, by parents as well as by teachers, that 

 they need no advocacy on the present occasion. But it 

 may be doubted whether sufficient attention has been bestowed 

 on the combination with Mathematical acquirements, of a 

 knowledge of the principles and substances belonging to the 

 material world, of which the forms and quantities which it is 

 the province of the Mathematician to investigate, so far as 

 they have a real existence, are merely the properties or attri- 

 butes. The inadequacy of the attention hitherto given to this 

 subject, so far as School-education is concerned, is connected, 

 probably, with the supposition, that instruction in the Mathe- 

 matics conveys a much more extensive knowledge of nature, 

 or of the Physical Sciences, than is actually the case. This 

 supposition may have arisen from the circumstance, that the 

 higher departments of Mathematical knowledge, in some 

 branches, are almost necessarily interwoven, in tuition, with 

 Astronomy and Natural Philosophy. It is the fact, however, 

 that a small portion, only, of Astronomical science, can be thus 

 taught ; and the other branches of Natural Philosophy com- 

 monly interwoven with the more advanced propositions of Al- 

 gebra and Geometry, include little more than elementary Me- 

 chanics, and certain laws or problems in Hydrodynamics and 

 Pneumatics. That considerable attainments may be made in 

 pure Mathematics, in the doctrines of quantity and of figured ex- 

 tension, without any enlarged acquaintance with the phsenomena 

 and history of nature, is a fact to which every man of science 

 will give his testimony. One object of the present memoir, 



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