386 M E M O IK S of the 
the fubflance we eat is not hard, but is eafily penetrated and 
divided, then the Incifores are capable of making an impreflion 
upon it, and for that purpofe they are firmly fixed in the jaw 
to break oft' the part they lay hold on , but if it be more fo- 
lid, and not eafily penetrated, and that a piece cannot be fepa- 
rated without difficulty from that body, whereof it is a part, 
then wts apply the iDentes Canini or eye-teeth to it, which are 
not fo broad, nor have fuch an edge as the Incifores^ but are 
/harp and pointed like an awl, and fo do more readily penetrate 
a hard lubftance ^ and as the parts of a more folid body are 
commonly feparated with more difficulty, and as there muil be 
a greater ftrefs put upon thofe teeth which break it into pieces, 
fo thefe teeth, tho' they have but one fingle root, are much 
more firmly fixed in the jaws than the Incijores: Befides, the 
pofition of all thefe teeth is accommodated to their ufc, as be- 
ing placed oppofire to the aperture of the mouth, fo that they 
may be conveniently applied to the fubftance we are to eat, 
before it is broken, and when it is too large to be admitted 
within the mouth ; the teeth which by comprefTion and attri- 
tion reduce the little morfels to fmaller parts, are from the 
manner in which they break the aliment, called 2)entes Mo- 
lares^ becaufe they grind, like fo many little mill-ftones, the 
food between them ^ and that they might be rendred fit for 
this purpofe, they are made broad at that extremity, which 
ftands out of the gums, by which means they retain fome 
quantity of the food between them, every time the lower jaw 
is pulled up and forced againft the Maxilla fuperior-y and as 
they are broad, fo they arc formed with inequalities and protu- 
berances, and by the motion of the lower jaw from one fide 
towards the other, they grind what lies between them into 
pieces; the pofition of thefe teeth is like wife as convenient as 
that of the Incifores and the 2)entes Canini -^ for being defigned 
to break the pieces of folid food, which are taken into the 
mouth, and theie pieces, when comprefTed and moved by the 
Rentes Molares^ being apt to fly out of the mouth, if there 
was no contrivance to prevent it, the Molares are placed be- 
vond the aperture of the mouth and oppofite to the cheeks, 
keep the food witliin that cavity 5 and not only fo, but preis it 
in between the 2)entes Molares on one fide, as the tongue docs 
on the other, until they have fufficiently comminuted and 
divided It: At the iame time, whilfl t\\Q T^entes Molares ^xq 
breaking the food, there flows into the mouth a falival juice, 
which niixes with it, and not only ferves to moiften and render 
it 
