Min] AND SYMBOLS. 229 



The Vast in the Minute. 



We discourse about the little and the great; but these are 

 relative terms. A thing which we may call little a philosopher 

 may declare contains in itself the basis of all life and the germ 

 of worlds. Take, for instance, such an insignificant thing as 

 the stinging nettle which you are about to tread beneath your 

 feet. Professor Huxley will speak with you about that nettle 

 in a manner which will invest it with astonishing interest for 

 evermore. He commences by telling you that that common 

 nettle owes its stinging property to the innumerable stiff and 

 needle-like though exquisitely delicate hairs which cover its 

 surface ; that each stinging-needle tapers from a broad base to a 

 slender summit, which, though rounded at the end, is of such 

 microscopic fineness that it readily penetrates and breaks off in 

 the skin. The whole hair, he says, consists of a very delicate 

 outer case of wood, closely applied to the inner surface of which 

 is a layer of semi-fluid matter, full of innumerable granules of 

 extreme minuteness. This semi-fluid is protoplasm (the physical 

 basis of life), which thus constitutes a kind of bag full of a limpid 

 liquid, and roughly corresponding in form with the interior of 

 the hair which it fills. When viewed with a sufficiently high 

 magnifying power, the protoplasmic layer of the nettle hair is 

 seen to be in a condition of unceasing activity. Local contrac- 

 tions of the whole thickness of its substance pass slowly and 

 gradually from point to point, and give rise to the appearance of 

 progressive waves, just as the bending of successive stalks of 

 corn by a breeze produces the apparent billows of a corn-field. 

 But in addition to these movements, and independently of them, 

 the granules are driven in relatively rapid streams through 

 channels in the protoplasm which seem to have a considerable 

 amount of persistence. Most commonly the currents in adja- 

 cent parts of the protoplasm take similar directions, and thus 

 there is a general stream up one side of the hair and down the 

 other. But this does not prevent the existence of partial 

 currents which take different routes ; and sometimes trains of 

 granules may be seen coursing swiftly in opposite directions, 

 within a twenty-thousandth of an inch of one another ; while, 

 occasionally, opposite streams come into direct collision, and after 



