ing to the half of the body that is paralyzed, loses, likewise, the power 

 of motion; the other retains its mobility, and draws the tongue towards 

 that side. In carcinoma of the tongue, one side remains unaffected by 

 the affection which destroys the other half; lastly, the arteries and nerves 

 of the left side rarely anastomose with those on the right ; injections 

 forced along one of the ranine arteries, fill only the corresponding half 

 of the organ, Sec. 



CXXX. Of tfo touch. No part of the surface of our body is exposed 

 to receive the touch of a foreign body, without our being speedily in- 

 formed of it. If the organs of sight, of hearing, of smell, and of taste, 

 occupied only limited spaces, touch resides in all the other parts, and ef- 

 fectually watches over our preservation. The touch distributed over the 

 whole surface, appears to be the elementary sense, and all the others are 

 only modifications of it, accommodated to certain properties of bodies. 

 All that is not light, sound, smell, or flavour, is appreciated by the touch, 

 which thus instructs us in the greater part of the qualities of bodies 

 which it concerns us to know, as their temperature, their consistence, 

 their state of dryness or humidity, their figure, their size, their distance, 

 Sec. It corrects the errors of the sight and of all the other senses, of 

 which it may justly be called the regulator, and it furnishes us with the 

 most exact and distinct ideas. 



The touch of which some authors have sought to consecrate the excel- 

 lence, by giving it the name of the geometrical sense, is not, however, 

 safe from all mistake. Whilst it is employed on the geometrical pro- 

 perties, derived from space, and that it appreciates the length, the breadth, 

 the thickness the form of bodies, it transmits to the intellect, rigorous 

 and mathematical results ; but the ideas we acquire, by its means, on. the 

 temperature of bodies, are far from being equally precise. For, if you 

 have just touched ice, another body colder than yours, will appear warm. 

 It is for this reason, that subterraneous places appear warm to us during 

 winter. They have kept their temperature whilst all things else have 

 changed theirs ; and as we judge of the heat of an object by its relation 

 not only to our own, but also to that of other bodies and of the air about 

 us, we find the same places warm which has appeared cold to us, in the 

 middle of summer. 



The densest bodies being the best conductors of heat*, marble, metals, 

 8cc. appear colder to us than they really are, because they carry it off so 

 rapidly. Marble and metals, when polished, appear still colder, because, 

 as they touch the skin in many more points at once, they affect this ab- 

 straction more effectually. Every one knows the experiment of placing 

 a little ball between the two fingers crossed, and producing the sensation 

 of two different balls. 



CXXXI. Of the integuments. The general covering of the whole body 



* Woolly substances, &c. all felts, of which the crossing hairs confine, in some sort, 

 a great quantity of air, a fluid which from its gaseous state, is a very bad conductor of 

 heat, retain heat well -.and, of equal thickness, a stuff of tine wool, of which the hairs 

 are more separated, the tissue softer, will be warmer than a stuff of coarse wool, of 

 which the threads, too close, form a dense body, through which cold as well as heat, 

 will pass with ease. It is by thus confining a certain mass of air, that snow keeps the 

 soil it covers, in a mild temperature, and preserves plants from the injury of excessive 

 cold; a physical truth which is found figuratively expressed, in the words of the Psalm- 

 ist, Et dcdit ilti nivemjkanquam vestimentiim. Gutter's JVbte. 



