TRANSACTIONS OF THE SECTIONS. 97 



present means of examination, structureless. Yet, although this may be the case, 

 it would be a great error to suppose that there is not much work yet to be done in 

 the more obvious department of Descriptive Anatomy which chiefly occupied 

 older investigators. Every year seems to show this, from the researches of culti- 

 vated Palaeontologists and Naturalists in every department : for both in this country 

 and on the two continents additions are being unceasingly made to the stock 

 of knowledge either of objects wholly new, or of objects or parts heretofore incom- 

 pletely described. 



For the purposes of the great scientific question of this age, the Causes of the 

 present order of Life on the Globe, it would seem that the minutest accepted data 

 of biological conclusion may have to be revised under new methods. It is a 

 saying among painters, " that a draughtsman sees no more than he knows." It is 

 true in the same way in Natural Science, that the real signification of a known 

 fact may be concealed for ages. Of this, Pathology offers many examples. The 

 older naturalists, notwithstanding the great learning of such men as Linnasus and 

 Haller, had comparatively either very simple or hypothetical and incorrect notions 

 of the complexities of living Beings and their constituent parts. Chemistry, the 

 Microscope, and the search for the Origin of Species have, in this century, widened 

 the horizon of biological study in a way not less surprising than does the dawn of 

 day to a traveller, who, having by night ascended some lofty peak, sees gradually 

 unfolding an extent and detail of prospect which he can generally survey, though 

 he cannot hope to verify each detail and visit every nook in the brief time allotted 

 to him for travel. The desire " rerun cognoscere causas " urges him even more 

 keenly than to know the things themselves. Thus in Biology, the laws of the 

 genesis of every known organic being have now become as much the object of 

 investigation as was once the nature of the being itself. The existence of defi- 

 nite species or varieties was formerly assumed in an arbitrary manner to be a kind 

 of necessity. The search after the laws which produced those species, and the 

 signification of them, has become as ardent as was once the definition of the spe- 

 cific characters. But it is a far more difficult pursuit, and requires either a very 

 special education, or remarkable natural powers. The difficulty pervades every 

 department of Biology in gross and in detail. Darwin seeks the solution for the 

 whole kingdom of nature. The Histologist, the Pathologist, the Organic Chemist 

 approaches it in the detail of every mechanical texture, and of every organic 

 chemical compound. We are apt to look on the Museum of John Hunter as the 

 most philosophic and extensive exposition of Biological Science in this or any 

 other country. And justly so. Inquiring originally into what is the proper 

 treatment of disease, he asks in order, What is its nature ? what its cause ? how 

 are the functions disordered ? how are they performed in health ? by what me- 

 chanism ? how is this mechanism varied F whence did it originate ? But compare 

 with his knowledge the knowledge of biologists of the present period viewed col- 

 lectively : take our knowledge of the ovum, for instance, and its development, 

 or the minute anatomy of the tissues, or (may I venture to use the epithet for so 

 vast a collection of ascertained truth ?) the nascent chemistry of living structures, 

 or the relations of osseous structures in the Vertebrata. It were hard to say which 

 is the more remarkable, Hunter's comprehensiveness, or the detail of modem 

 science. Yet how many details are still needed for a safe Biological Philosophy. 



Yet are we only on the threshold of detailed knowledge. We still speak of 

 many hard points with an almost childlike simplicity. What do we understand, 

 for instance, of the cause of that which Herbert Spencer calls "Organic Polarity"— 

 that is to say, the power, force, or tendency by which lost parts are repaired" — by 

 which a whole limb — or part of a limb — or even all but a whole body is replaced 

 by the outgrowth from what remains of the original unmutilated whole — a process 

 so common in Asteriadne and Crustacea and other animals as to seem a matter of 

 course in their history, while it is apparently a property which cannot exist in the 

 higher animals ? What do we know of the causes of hereditary transmission in 

 general (a property wholly different from, and more unintelligible* than the hypo- 

 thesis of natural selection), or of the transmission of disease in particular, as for 

 example, of Carcinoma ? What is it in its essence ? How does it originate in 

 an individual of untainted family? How is it transmitted? Is it an original 

 - 1865. 7 



