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Universal Dictionary

OF

KNOWLEDGE,

COLLECTED FROM EVERY SOURCE:

AND INTENDED TO

SUPERSEDE THE USE OF ALL OTHER ENGLISH BOOKS OF REFERENCE.

Jllustrated with plates and maps.

IN TWENTY THRFE VOLUMES.

VOLUME XV.

PERTH:

PRINTED FOR C. MITCHEL AND CO.

AND SOLD FOR THEM BY MR THOMAS OSTELL, AVE MARIA LANE, LONDON.

SOLD ALSO BY MESS. VERNOR, HOOD, AND SHARPE, LONDON;

AND ALL RESPECTABLE BOOKSELLERS.

R. Morison, Printer.

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ENCYCLOPÆDIA PERTHENSIS:

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M IN

MIN
ME
INE. rif{mine, French; mwyn or bife is double the height taken from the centre,
mun,

Well, from maen lapis, in the of the mine. 4. That when the mine has been pliiamaail. 1. A place or cavein in the earth overcharged, its entonnoir is nearly cylindrical, Nicotics metais or minerals.--

the diameter of the upper extreme not much exlas ycui large heart was found a wealthy mine. ceeding that of the chainber. 5. That besides the

Waller. fhock of the powder against the bodies it takes upg, - workman, to avoid idlencsi, worked in a it likewise crushes all the earth that borders upon FOI maino.pit thereabouts, which was little it, both underneath and fidewise. To charge a cant. Burke A mine-digger may meet with a mine so as to have the most advantageous effect, the xoti, ne de knows not what to make of. Bolez weight of the matter to be carried must be known; -The bee dui mine-man aims only at the obtain that is, the folidity of a riglit cent', whoie base is

a quarts cf ich a metal as may be verdible. double the height of the earth over the centre of 2.2. Årsvern dag under alle fortification the mine: thus, having found the folidity of the *.cites & tür waot of fuppoit; or, in mo- core in cubic frihenis, multiply the number of 2 70t, that powder may be lodged in it, which fathons by the number of pounds of powder nen hised at a proper time, whatever is over it cuirry for raising the matter it contains; and if How! ! mid detroyed.

the cone contains matters of different weights, mine lidih cilt thrown down fo fair a take a mean weight between them ail, always had 10*er?

Silnel'. ving a regard to their degree of cohesion. As to the -3... up the walls of Jerusalem, which you o disposition of mines, there is but one general rule, die erken down, and fill up the mines that you viz. that the hide towards which one would deter: Asted. Wbiigis.

mine the elect be the weaket; but this varies Others tu a city strong

according to circumstances. The calculation of L' Beze, encamp’d; by batt'ry, scale and mine, mines is generally built upon this hypothesis,

Milton. That the entonhoir of a mine is the fruitum of an 11. Mi, in the military art, (§ 1. dif. 2.) inverted cone, whose altitude is equal to the raSet Miss Il. in latt volume, p: 720.

Fron dius of the excavation of the mine, and the dia. 4 Pcsi Tumber of experiments, it appears, 1. meter of the whole eller base is equal to the line Truthe force of a mine is always towards the of lealt retistance'; and though these fuppofitions sakit ite; so that the difpofition of the cham- are not quite exact, yet the calculations of mines RT0, a mine docs vot at all contribute to deter- deduced from them have proved fucecf fal ini 11.2. this efect. 2. That the qumtity of pow. practice ; for which reaton this calculation thould

mit be greater or less in proportion to the be followed till a better and more fimple one Te r'ct ur leis weight of the bodies to be raised, be found out. M. D. Valliere found that the 21 tu ticis greater or less cohesion; to that we entonnoir of a mine was a p.rabaloid, which is a 7*** alue for each cubic fathom, of loose eartl!, folit generated by the rotation of a femiparabola 9 44 10h. Of firm earth and strong sind, 11 or about its axis; but as the difference between is ib. Oi Mat clayey carth, 15 or iú ib. Of new these two is very insignificant in practice, that of Datuiry, not strongly bouni, 15 or 20 lb.; and the frulum of a cone may be used. c old malonty, weil bound, 25 or 30 lb. 3.

(III. 1.) Mine in natural history, ( II. def. 1.) Toa the aperture, or entonnoir of a mine, if rights implies a deep pit under ground, whence various is charged, is a cone, the diameter of whose kinds of minerals are dug out; but is more partiVOL. XV. PARTI.

A

cularly

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