LECTURES AND ESS A YS 



and while to the one the last bold defence 

 and startling expansion of the doctrine 

 by Dr. Bastian will appear perfectly con- 

 clusive, to the other it will present itself 

 as merely imposing a labour of demo- 

 lition on subsequent investigators. 1 



Let me say here that many of our 

 physiological observers appear to form a 

 very inadequate estimate of the distance 

 which separates the microscopic from 

 the molecular limit, and that, as a con- 

 sequence, they sometimes employ a 

 phraseology calculated to mislead. When, 

 for example, the contents of a cell are 

 described as perfectly homogeneous or 

 as absolutely structureless, because the 

 microscope fails to discover any struc- 

 ture; or when two structures are pro- 

 nounced to be without difference, because 

 the microscope can discover none, then, 

 I think, the microscope begins to play a 

 mischievous part. A little consideration 

 will make it plain that the microscope 

 can have no voice in the question of 

 germ structure. Distilled water is more 

 perfectly homogeneous than any possible 

 organic germ. What is it that causes 

 the liquid to cease contracting at 39 

 Fahr., and to expand until it freezes? 

 We have here a structural process of 

 which the microscope can take no note, 

 nor is it likely to do so by any con- 

 ceivable extension of its powers. Place 

 distilled water in the field of an electro- 

 magnet, and bring a microscope to bear 

 upon it. Will any change be observed 

 when the magnet is excited? Absolutely 

 none ; and, still, profound and complex 

 changes have occurred. First of all, the 

 particles of water have been rendered 

 diamagnetically polar ; and secondly, in 

 virtue of the structure impressed upon it 

 by the magnetic whirl of its molecules, 

 the liquid twists a ray of light in a fashion 

 perfectly determinate both as to quantity 

 and direction. 



Have the diamond, the amethyst, and 

 the countless other crystals formed in 



1 When these words were uttered I did not 

 imagine that the chief labour of demolition would 

 fall upon myself. 1878. 



the laboratories of nature and of man no 

 structure ? Assuredly they have ; but 

 what can the microscope make of it? 

 Nothing. It cannot be too distinctly 

 borne in mind that between the micro- 

 scopic limit and the true molecular limit 

 there is room for infinite permutations 

 and combinations. It is in this region 

 that the poles of the atoms are arranged, 

 that tendency is given to their powers; 

 so that when these poles and powers 

 have free action, proper stimulus, and a 

 suitable environment, they determine, 

 first the germ, and afterwards the com- 

 plete organism. This first marshalling 

 of the atoms, on which all subsequent 

 action depends, baffles a keener power 

 than that of the microscope. When 

 duly pondered, the complexity of the 

 problem raises the doubt, not of the 

 power of our instrument, for that is nil, 

 but whether we ourselves possess the 

 intellectual elements which will ever 

 enable us to grapple with the ultimate 

 structural energies of nature. 1 



In more senses than one Mr. Darwin 

 has drawn heavily upon the scientific 

 tolerance of his age. He has drawn 

 heavily upon time in his development of 

 species, and he has drawn adventurously 

 upon matter in his theory of pangenesis. 

 According to this theory, a germ, already 

 microscopic, is a world of minor germs. 

 Not only is the organism as a whole 

 wrapped up in the germ, but every organ 

 of the organism has there its special seed. 

 This, I say, is an adventurous draft on 

 the power of matter to divide itself and 

 distribute its forces. But, unless we are 

 perfectly sure that he is overstepping the 

 bounds of reason, that he is unwittingly 



1 " In using the expression, ' one sort of living 

 substance,' I must guard against being supposed 

 to mean that any kind of living protoplasm is 

 homogeneous. Hyaline though it may appear, 

 we are not at present able to assign any 

 limit to its complexity of structure." Burdon 

 Sanderson, in the British Medical Journal, 

 January loth, 1875. We have here scientific 

 insight, and its correlative caution. In fact, 

 Dr. Sanderson's important researches are a 

 continued illustration of the position laid down 

 above. 



