PROVINCIAL INSTITUTIONS AND SOCIETIES. 
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The process consists in heating the powdered mineral, with common salt and 
sodium, for two hours in a covered crucible ; at its conclusion the metal is 
found at the bottom of the slag. The price of the metal, when it was first 
obtained, was £5 to £6 per ounce. In 1806 Deville had reduced it to 
T3 per ounce, and it is now usually worth 5s. per ounce, although Mr. 
Gerhard, who is engaged in preparing the metal from cryolite on a large 
scale at Battersea, stated at a meeting of the Society of Arts, that he had 
undertaken a contract at 3s. 9d. per ounce. 
“ Aluminium is a white metal, with a bluish tinge, and a lustre inferior to 
that of silver. Its specific grav. is 2’6, or about one fourth that of silver, a 
property of importance, as this lightness causes a given weight of aluminium 
to go as far in the manufacture of articles as four times the quantity of silver. 
It is malleable, and ductile, and possesses considerable tenacity ; when pure, 
it is as hard as silver, but it has no great elasticity, and requires rather a high 
temperature to fuse it. It is not oxidized by exposure to air, even at high 
temperatures ; it resists the action of sulphur and sulphuretted hydrogen, 
which so rapidly tarnish silver, and is insoluble in any of the ordinary acids, 
except the muriatic ; potass, soda, and ammonia in solution dissolve it 
rapidly ; and the beautiful frosted appearance seen on articles manufactured 
of aluminium is produced by plunging them for a short time in a solution of 
potass at blood-heat, and then immersing them in nitric acid. 
“ It will easily be seen that a metal possessing the properties above de- 
scribed will be capable of many applications, and aluminium has already been 
employed in the manufacture of a great number of articles. Its chief use, 
however, will probably be in the production of alloys, as it gives increased 
hardness to whatever metal it is used with. An alloy of three parts alu- 
minium and 97 parts iron has the brilliancy of pure silver, and does not 
tarnish. 100 parts silver and 5 parts aluminium form an alloy as hard as 
sterling silver, and as easily worked as the pure metal. Copper, with a 
quarter of its weight of aluminium, gives an alloy of the colour of gold, and 
very malleable. With 20 per cent, of aluminium the alloy is white ; and a 
mixture of 90 parts copper and 10 parts aluminium is harder than bronze, 
and has been used for the works of clocks and watches. Calvert describes 
an alloy of 15 aluminium and 78 iron, which does not rust in moist air or 
water.” 
Another paper of deep interest was read, April 2nd, by the Rev. J. Kenrick, 
on the Rev. Mr. M'Enery’s “ Researches in Kent’s Hole, near Torquay.” 
Bearing, as it does, upon the supposed age of the human race, and expressing 
the opinions of an enlightened clergyman and antiquary, we recommend it to 
the careful consideration of our readers : — 
“ Kent’s Hole is a fissure in the limestone rock, which belongs to the Old 
Red Sandstone formation. Its floor is covered with a stalagmitic deposit, 
under which lies a bed of mud and gravel, brought in by a flood of water. 
According to Mr. M'Enery, the various contents of the cave follow each other 
iii this order, proceeding downwards froip the surface. First, black pottery, 
with traces of the lathe, human teeth and bones, beads, bone pins, and other 
articles belonging to the Romano-British period, when the Romans had an 
encampment on the down above the cave. Lower down were found arrows 
and spear-heads of flint, and stone axes, among fossil teeth and bones of her- 
bivorous and carnivorous animals, but no pottery or other works of art ; 
lowest of all the bed of diluvial mud, containing merely animal remains, but 
no works of art, except some flint instruments adhering to its upper surface. 
Mr. M^Eneiys description of the succession of deposits, however, has been 
called in question by a geologist of great eminence, Mr. Godwin Austen, who 
maintains that the human remains and the arrow-heads and knives of flint 
