Oil, A TREATISE ON PILE. 



Description of an Instrument called a Trichometer,* designed 

 to measure the Ductility, Elasticity and Tenacity of Pile. The 

 accompanying figure represents a brass plate, 3 and ^ inches 

 long and 1 ^ wide. A, is an inch scale divided on the margin 

 into parts of an inch. By means of a slide and groove this scale 

 can be moved up and down, not exceeding one inch, the parts of 

 which are marked on the brass plate; B, is a permanent clamp, 

 and C a moveable one ; D, is a separate clamp, with a hook by 

 which the scale disk is suspended. 



Modus operandi. Having ascertained the state of the barome- 

 ter, thermometer and hygrometer, place one end of a hair, some- 

 thing more than an inch long, in the clamp C, and the other 

 (Mid into clamp D; adjust, with the screw of C, until there is 

 exactly one inch of hair from the points of clamp D, (between 

 which it passes,) and the jaws of clamp B ; close both these 

 clamps. Having placed the instrument in a vertical position, 

 suspended the scale disk to the hook, and put into it as much 

 weight as will cause the pile to stretch, note the amount, as 

 indicated by the scale, f remove the weight, and ascertain to 

 what degree the pile returns to its original length by means of 

 its elasticity. Repeat the experiment with gradually increased 

 weights until the hair breaks. These results will show the ductility, elasticity and 

 tenacity. 



OF THE DIRECTION OF PILE. By direction we mean the course or path which a 

 filament of pile pursues from the point where it pierces the epidermis to its apex. These 

 directions are of three kinds, viz: 1st, the straight and lank;J 2d, the flowing or curl- 

 ing; 3d, the crisped or frizzled, which is generally spirally curled. $ 



The Laws Relating to the Direction of Pile. 1. Hair that is cylindrical must necessarily 

 hang straightly and lankly from the head. 2. Hair that is oval must inevitably flow 

 or curl. 3. Wool that is eccentrically elliptical must always be crisped or frizzled, and 

 sometimes spirally curled. 



The Reasons. Ductility and elasticity, (as before explained,) are essential properties of 

 pile, and reside in the fibres. A hair that is cylindrical has just as many fibres, on all 

 sides, from the centre to the periphery ; and these fibres, being acted upon equally, when 

 the hair is stretched or drawn up, the filament must necessarily stretch and draw up 

 straightly, and the lankness be preserved. But an oval hair has a greater number of fibres 

 on its two flattened sides than upon the ellipses; when, therefore, the stretching power is 



* From " trix," a hair, and "mctron," a measure. 



t The weight of the clamp I), and scale disk must be added. 



J " Lank." We know of no word in the English language which gives a better idea of the peculiar direction of this pile. 



| Query, whether crisped and frizzed pile is not spiral curls drawn out and combed separate? 



