DIV 



DIV 



Thus lar we have shown that exten- 

 sion may be divided into an unlimited 

 number of parts; but with respect to the 

 limits of the divisibility of matter itself, 

 we are perfectly in the dark. We can 

 indeed divide certain bodies into sur- 

 j ir'./.i ugly fine and numerous particles, 

 ami the works of nature offer many fluids 

 and solids of wonderful tenuity ; but 

 both our efforts, and those naturally 

 small objects, advance a very short way 

 towards infinity. Ignorant of the inti- 

 mate nature of matter, we cannot assert 

 whether it may be capable of infinite di- 

 vision, or whether it ultimately consists 

 of particles of a certain size, and of per- 

 fect hardness. We shall now add some 

 instances of the wonderful tenuity of cer- 

 tain bodies, which have been produced 

 either by art, or discovered by means of 

 microscopical observations, amongst the 

 stupendous works of nature. 



The spinning of wool, silk; cotton, and 

 such-Iikc substances, alFords no bad spe- 

 cimens of this sort; since the thread 

 which has been produced by this means 

 has often been so very fine, as almost to 

 exceed the bounds of credibility, had it 

 not been sufficiently well authenticated. 

 Mr. Boyle mentions that two grains and 

 a half of silk were spun into a thread 300 

 yards long. A few years ago, a lady of 

 Lincolnshire spun a single pound of wool- 

 len yarn into a thread of 168,000 yards 

 long, which is equal to 95 English miles. 

 Also a single pound weight of fine cotton- 

 yarn was lately spun, in the neighbour- 

 hood of Manchester, into a thread 134,400 

 yards long. 



The ductility of gold likewise furnishes 

 a striking example of the great tenuity of 

 matter amongst the productions of human 

 ingenuity. A single grain weight of gold 

 has been often extended into a surface 

 equal to 50 square inches. If every 

 square inch of it is divided into square 

 particles of the hundredth part of an 

 inch, which -will be plainly visible to the 

 naked eye, the number of those particles 

 in one inch square, will be 10,000 ; and 

 multiplying this number by the 50 inches, 

 the product is 500,000; that is, the 

 grain of gold may be actually divided 

 into at least half a million of particles, 

 each of which is perfectly apparent to 

 the naked eye. Yet, if those particles 

 are viewed in a good microscope, they 

 will appear like a Targe surface, the ten- 

 thousandth part of which might by this 

 means be easily discerned. An ingenious 

 artist in London has been able to draw 

 parallel lines upon a glass plate, us also 



VOL. IV. 



upon silver, so near one another, that 

 10,000 of them occupy the space of one 

 inch. Those lines can be seen only by 

 the assistance of a very good microscope. 

 Another workman has drawn a silver 

 wire, the diameter of which does not 

 exceed the 750th part of an inch. But 

 those prodigies of human ingenuity will 

 appear extremely gross and rude, if they 

 are compared with the immense subtilty 

 of matter which may every where be ob- 

 served amongst the works of nature. 

 The animal, the vegetable, and even the 

 mineral kingdom, furnish numerous ex- 

 amples of this sort. What must be the 

 tenuity of the odoriferous parts of musk, 

 when we find that a piece of it will scent 

 a whole room in a short time, and yet it 

 will hardly lose any sensible part of its 

 weight ! But supposing it to have lost 

 one-hundredth part of a grain weight, 

 when this small quantity is divided and 

 dispersed through the whole room, it 

 must so expand itself as not to leave an 

 inch square of space where the sense of 

 smell may not be affected by some of its 

 particles. How small must then be the 

 weight and size of one of those particles ! 

 The human eye, unassisted by glasses, 

 can frequently perceive insects so small 

 as to be barely discernible. The least re- 

 flection must show, that the limbs, the 

 vessels, and other parts of such animals, 

 must infinitely exceed in fineness every 

 endeavour of human art. But the mi- 

 croscope has discovered wonders that 

 are vastly superior, and such indeed as 

 were utterly unknown to our forefather!, 

 before the invention of that noble instru- 

 ment. 



Insects have been discovered so small, 

 as not to exceed the 10,000th part of an 

 inch : so that 1,000,000,000,000 of them 

 might be contained within the space of 

 one cubic inch ; yet each animalcule must 

 consist of parts connected with each 

 other; with, vessels, with fluids, and with 

 organs necessary for its motions, for its 

 increase, for its propagation, Stc. How 

 inconceivably sma!l must those organs 

 be ! and yet they are unquestionably 

 composed of other parts still smaller, and 

 still farther removed from the perception 

 of our senses. 



DIVISION, in general, is the separat- 

 ing a thing into two or more parts. Al- 

 though the mechanical division of bodies 

 separates them into smaller parts, it can- 

 not extend to the primary particles of any 

 body, and is, consequently, incapable of 

 breaking what is called the aggregation. 

 Division is also reckoned nmongthc terms 

 Dd 



