M I L 
388 M 1 L 
the vein dilappears. It is every-where the higheft ftra- 
tum • and, when difengaged from the quarry where now 
worked it tumbles down the fide of the mountain to the 
ulain within five hundred yards of the Ihipping-place, 
where fmall veffels may lie lately in all weathers at a na¬ 
tural quay, completely calculated for this bufinefs. The 
quarry lies on the decline of a hill: the vein now is about 
eiaht yards wide ; but he has reafon to fuppole it wider 
below At the depth he has lunk, which is at leaft twen¬ 
ty-five feet, the ftone mends in quality. When firft taken 
from the quarry, it is much fofter, and eafier wrought into 
ihape than when expofed to the air : even a day makes a 
difference. The vein appears to him quite mexhauftible, 
and contains every variety of the ftone, cellular or dole, 
iiard or loft. The right in this trad of country had been 
prefented to him, by Mr. Sneyd of Staffordfliire, under the 
hope that he might be able to make this difcovery, and 
can-y it vmoroully into effeCl; in which he has not been 
dil'ippointed. It would appear from the evidence fent to 
the Society for the Encouragement of Arts, &c. that the 
ftones railed from this quarry are capable of being em¬ 
ployed in molt cafes where tliofe imported from France 
have been in ufe; and that the ftone, from its external ap¬ 
pearance, lee ms to be conftituted of quartz and cherts. 
r And in the latter fituation, 1. e. in Scotland, ftones fit 
for this ufe were difcovered by James Brownhill, miller; 
who when the late unfortunate war had rendered the get- 
tino-’of the French burr extremely difficult, as he was 
pafllno- by the great bafaltic rock of the Abbey Craig, 
near Stirling, examined the texture ot leveral maffes of 
the ftones : "he found one lpecies which appeared to him 
fit for the grinding of wheat, and brought home a fample, 
which he lhowed to Mr. Alexander Ball, agent of the 
Alloa Mills, who agreed to make trial of a pair. They 
were put up under his direction in the lame manner as 
the French burr; and, on their being fet to work, gave 
fuch fatisfaclion to the cuftomers of the mills, as induced 
the Alloa Mill Company to have another pair, and totally 
to lay afidethe French burr mill-ftones. Ic is luggelted, 
that the French burr-ftones are fo porous, as to make it 
ne'cefl'ary to fill up the cavities with a preparation of alum ; 
this conliderable expenle is faved by the uniform texture 
of the bafaltes ; and their fuperior excellence is fo appa¬ 
rent, that upwards of lixty pair are now at work in leve¬ 
ral parts of the kingdom ; and the demand lor them is 
daily increafing. In addition it is ftated, that the bafaltes 
mill-ftones are not only excellent for manufaCluring of 
flour, but for all kind of grift. The diftillers give them 
a decided preference; and they grind oats in a very com¬ 
plete ftyle, as the meal is returned quite free of fand; 
which is a great delideratum lor tliofe places wheie oat- 
bread is in ufe. It may be noticed, that, in the. lormei of 
the above quarries, mill-ftones are railed which are of 
much larger fizes than the French burrs, which may pro¬ 
bably be an advantage in fome cafes. 
The following remarks are offered by Mr. Fergufon on 
the fize and velocity of mill-ftones. The diameter of the 
upper ftone is generally about fix feet, the lower ftone 
about an inch more ; and the upper ftone, when new, 
contains about nai cubic feet, which weighs lbmewhat 
more than 19,000 pounds: A ftone of this diameter ought 
never to go more than 60 times round in a minute ; lor, 
if it tarns fafter, it will heat the meal. But, according to 
Mr. Imifon, the mill-ftone fliould turn twice round in a 
fecond of time, and fliould only be four feet and a half in 
diameter. It may probably be imagined, that the meal 
will be much heated by fuch a rapid motion as he has re¬ 
commended ; but the effeCl is counteracted by diminilhing 
the fize of the mill-ftone from fix feet to four and a halt. 
The velocity of the circumference of the lmall mill-ftone 
moving twice round in a fecond, is only one-third greater 
than the velocity of the large mill-ftone moving once 
found in a fecond. 
The inode of preparing mill-ftones for the purpofe of 
blinding has been delcribed under the article Mechanics, 
vol. xiv. p. 684. Fig. 8. of the preceding Plate, represents 
the furface of the under mill-ftone ; the way of laying out 
the wads or channels 5 the wooden bufh is fixed into the 
hole in the middle, in which the upper end of the iron 
fpindle turns round ; and the cafe or hoops that furround 
the upper one, which ought to be two inches clear of the 
ftone all round its circumference. Fig. 9. fhows the up¬ 
per mill-ftone, and iron crofs or rynd in its middle, in the 
centre of which is a fquare hole that takes in a fquare on 
the top of the iron fpindle, to carry the mill-ftone round. 
When the working ildes or faces of the mill-ftones are 
laid uppermoft, the wads muft lie in the fame direction 
in both, that, when the upper ftone is turned over, and 
its furface laid on the under one, then the channels crofs 
each other, which aftifts in grinding and throwing out the 
flour; the wads are alfo laid out according to they/ay 
that the upper ftone revolves. In thefe the running mill- 
ftone is fuppofed to turn Junways, or what is called a right- 
handed mill ; but, if the ftone revolves the other way, the 
channels muft be cut the reverfe of this, and then it is 
termed a left-handed mill. 
The mill-ftones which we find preferved from ancient 
times, are all fmall, and very different from thofe in ufe 
at prefent. Thorelby mentions two or three fuch found 
in England, among other Roman antiquities, which were 
but twenty inches broad; and there is great reafon to be¬ 
lieve that the Romans, as well as the Egyptians of old, and 
the ancient Jews, did not employ horfes, or wind, or wa¬ 
ter, as we do, to turn their mills, but made their flaves 
and captives of war do this laborious work. The runner, 
or loole mill-ftone, in this fort of grinding, was ufually 
very heavy for its fize, being as thick as broad. The Tal- 
mudifts have a ftory that the Chaldeans made the young 
men of the captivity carry mill-ftones with them to Baby¬ 
lon, where there feems to have been a fcarcity at that time ; 
and hence, probably, their paraph rale renders the text 
“ have borne the mills, or mill-ftones ;” which might 
thus be true in a literal fenfe. They have alfo a prover¬ 
bial expreflion of a man “ with a mill-ftone about liis 
neck ;” which they ufe to exprefs one under the fevered: 
weight of affliction. 
MILL'-TEETH, f. The grinders, dentes molares; dou¬ 
ble teeth.—The beft inftruments for cracking bones and 
nuts are grinders, or mill-teeth. Arbuthnot on Aliments. 
MIL'LACH, a town of France, in the department of 
the Charente : ten miles north of Confident. 
MIL'I.AH, a mountain of Algiers : fifteen miles fouth- 
weft of Tiffeflr. 
MIL'LAR (John), profeffor of law in the univerfity of 
Glalgow-, was born in 1735, in the parilh of Shotts, in La- 
markfhire. He received his grammar-education at the 
fchool of Hamilton, whence he was removed at the age of 
eleven to Glafgow. He was defigned for the church ; 
but, the freedom of his enquiries having infpired him 
with a difinciination to fetter himfelf by fubfcription to 
articles of faith, he turned his thoughts to the bar, and 
his father acquiefced in the change. After he had riniih- 
ed his ftudies at Glafgow, he paffed about two years in the 
family of lord Karnes as tutor to his Ion, and derived 
much information and improvement from his connection 
with that eminent lawyer. At this period he contracted 
an acquaintance with David Hume, to whole metaphyfi- 
cal opinions he became a convert, though he materially 
differed from him upon political topics. In 1760 Mr. 
Millar began to praCtife at the bar ; and was regarded as 
a riling young lawyer, when he thought proper fuddenly 
to terminate his profelfional career by becoming a candi¬ 
date for the vacant profefforlliip of law at Glalgow. To 
this poll he was appointed in 1761, and immediately be¬ 
gan to execute its duties. Previoufly to his appointment, 
the ftudents of the law-courfe feldom exceeded four or 
five in number; but his reputation produced fuch an ac- 
ceflion in a few years, that they frequently amounted to 
forty, and the pupils at his leCtures on government were 
much more numerous. He leCtured in Englilh, and fpoke 
fluently 
