MINE. 
tallic or of any other nature, are called the 
loads; when the substances forming these 
loads are reducible to metal, the loads are 
by the miners said to be alive ; otherwise 
they are called dead loads. In Cornwall 
and Devon, the loads always hold their 
course fiom eastwai-d to westward ; though 
in other parts of England, they frequently 
run from north to south. The miners re- 
port, that the sides of the load never bear 
in a perpendicular, but constantly under- 
lay, either to the north or to the south. 
The load is frequently intercepted by the 
crossing of a vein of earth, or stone, or 
some different metallic substance ; in which 
case it generally happens that one part of 
the load is moved a considerable distance 
to the one side. This transient load is by 
the miners called flooking : and the part 
of the toad which is to be moved, is said 
to be heaved. According to Dr. Nichols’s 
observations upon mines, they seem to be, 
or to have been, the channels through 
which the water pass within the eartli, and, 
like rivers, have their small branches open- 
ing into them, in all directions. Most 
mines have streams of water running through 
them; and when they are found dry, it 
seems to be owing to the waters having 
changed their course, as being obliged to 
it, eitlier because the load has stopped up 
the ancient passages, or that some new and 
more easy ones are made. Mines, says Dr. 
Shaw', are liable to many contingencies ; 
being sometimes poor, sometimes soon ex- 
haustible, sometimes subject to be drown- 
ed, especially when deep, and sometimes 
hard to trace ; yet there are many instances 
of mines proving highly advantageous for 
hundreds of years; the mines of Potosi are 
to this day worked with nearly the same 
guccess as at first; the gold-mines of Crem- 
nitz have been Worked almost these thou- 
sand years ; and our Cornish tin-mines are 
extremely ancient. The neat profit of the 
silver alone, dug in the Misnian silver-mines 
in Saxony, is still, in the space of eight 
years, computed at a thousand six hundred 
and forty-four millions, besides seventy- 
three tons of gold. Many mines have been 
discovered by accident ; a torrent first laid 
open a rich vein of the silver-mine at Fri- 
berg in Germany; sometimes a violent 
wind, by blowing up trees, or overturning 
the parts of rocks, has discovered a mine ; 
the same has happened by violent showers, 
earthquakes, thunder, the firing of woods, 
pr even tlie stroke of a plough-shai-e, or 
iiorse’s hoof. 
But tlie art of mining does not wait for 
these favourable accidents, but directly 
goes upon the search and discovery of such 
mineral veins, ores, or sands, as may be 
worth the working for metal. The prin- 
cipal investigation and discovery of mines 
depend upon a particular sagacity, or ac- 
quired habit of judging froTu particular 
signs, that metallic matters are contained 
in certain parts of the earth, not far below 
its surface. The principal signs of a la-, 
tent metallic vein, seems reducible to ge- 
neral heads, such as, 1. The discovery of 
certain mineral waters, g. The discoloura- 
tion of the trees or grass of a place. 3 . 
The finding of pieces of ore on the surface 
of the ground. 4. The rise of warm exhala- 
tions. 5. The finding of metallic sands, 
and the like. All which are so many en- 
couragements for making a stricter search 
near the places where any thing oPthis 
kind appears; whence rules of practice 
might he formed for reducing this art to a 
greater certainty. But when no evident 
mark of a mine appears, the skilful mine- 
ralist usually bores into the earth, in such 
places as from some analogy of knowledge, 
gained by experience, or by observing the 
situation, course, or nature of other mines, 
he judges may contain metal ; this method 
of boring we have already given under the 
article Boring. 
After the mine is found, the next thing 
to be considered is whether it may be 
dug to advantage. In order to determine 
this, we are duly to weigh the nature of 
the place, and its situation, as to wood, 
water, carriage, healthiness, and the like, 
and compare the result with the richness 
of the ore, tlie charge of digging, stamping, 
washing, and smelting. 
Particularly the form and situation of 
the spot should be well considered. A 
mine must either happen, 1. In a moun- 
tain. 2. In a hill. 3. In a valley. Or, 4. 
in a flat. But mountains and hills are dug 
with much greater ease and convenience, 
chiefly because the drains and burrows, 
that is, tlie adits or avenues, may be here 
readily cut, both to drain the water and to 
form gangways for bringing out the lead, 
.&c. In all the four cases we are to look 
out for the veins which the rains, or other 
accidental thing, may have laid bare ; and 
if such a vein be found, it may often be 
proper to open the mine at that place, es- 
pecially if the vein prove tolerably large 
and rich : otherwise the most commodious 
place for situation is to be chosen for the 
