326 QUARTZ FIBERS. 



Beiiiff then in this (iiHicjilty I was by good fortimo and necessity led 

 to devise a process wliicth 1 pi'oi)ose at once to show yon, 1 shall not 

 describe the preliminary experiments, bnt simply describe the process 

 as it stands. There is a small cross-bow held in a vice, and a little 

 arrow made of straw with a needle point, and I have here a fragment 

 of rock crystal which has been melted and drawn into a rod. It re- 

 quires a temperature greater than that developed in any furnace to 

 melt this material so that it may be drawn out. If the arrow, which 

 also carries a i)iece of the (piartz rod, is i)laced in the bow, and if both 

 pieces are heated up to the melting point and joined together, and then 

 the arrow is shot, a fiber of quartz is drawn, — that is to say, it is drawn 

 if there is not an accident. 



The arrow has tiown, and there is now a liber not very line this time, 

 which I shall hand to our iiresident. At the same time I can pass him 

 a piece of much liner fiber, made this afternoon, which shows (and this 

 is a proof of its fineness) all the brilliant colors of the spider line when 

 the sun shines upon it, but with a degree of magnificence and spleudor 

 which has never been seen on any natural ol)ject. 



The main featnres of these fibers are these. You can make them as 

 fine as you please ; you can make them of very considerable length; 

 you can make pieces 40 or 50 feet long, withont the slightest trouble, at 

 almost every shot. Even though of that great length, ihey are very 

 uniform in diameter from end to end, or at any rate the variation is 

 small and perfectly regular. The strength of the fiber is, T think I may 

 safely say, something astonishing. Fibers such as I have in use at the 

 present time in an instrument behind me are stronger than ordinary 

 bar steel ; they carry from 00 to 80 tons to the square inch. That is 

 one of their most important features, for this reason, — that on account 

 of their enormous strength you can make use of very much finer fibers 

 than wonkl be possible if they were not so strong; and I have already 

 explain(!d the importance of the tineness of the fiber when delicacy is 

 of the first importance. 



As to the diameter of these fibers, I have said thej' can be made as tine 

 as you please. I shall not trouble you with a large number of figures, 

 but one or two may jirobably be interesting to those who are in the 

 habit of using philosophical apparatus. In the first place, a fiber a 

 great deal finer that a single fiber of silk (that is, one five-thonsandth 

 of an inch in diameter), will carry an apparatus more than .JO grains 

 in weight. 1 have in one of the pieces of apparatus which 1 shall use 

 presently, a fiber the fifteen-thousandth of an inch in diameter. That 

 is, so fine that if you were to take a hundred of them and twist them 

 into a bundle you would i)roduce a compound cable of the thickness of 

 a single silkworm's thread. I do not m6an the silk used for sewing that 

 is wound on a reel, because that is composed of an enormous number 

 of silk threads ; but a single silkworm's thread as it is wound from the 



