THE MEDITERRANEAN NATURALIST 
307 
From Rock to Plant Food. — The process of con- 
version of granite into soil is thus summarized by 
Prof. A- Johnstone, of Edinburgh: Oxidation of 
iron is the first change perceivable; then creation 
and multiplication of weather joints, and carbo- 
nati in follows; next humus is formed by lichens 
and then higher plants; following this, fungoid 
germs, c >pable of assimilating aerial nitrogen, be- 
came abundant; finally all the three processes, me- 
chanical, chemical, and organic, go merrily on to- 
gether and contribute all in their proper shares to 
the formation of an ever-deepening soil capable 
of supporting the luxuriant life of the highest 
plants. 
Romance of Scotch. Science. — The development, 
of Scotland’s shale oil industry was mentioned 
in the president’s address to the late meeting in 
Edinburgh of the British Pharmaceutical Confer- 
ence. A few years ago the shale was looked upon 
as useless. From it are now obtained paraffin, lu- 
bricating and burning oils, and ammonia, more 
than £3,000,000 of capital being invested.- Lgst year 
55,000,000 gallons of crude oil were distilled from 
2,311,592 tons of shale. A curious incident in con- 
nection with this industry is that the desiging of 
the machinery for condensing the shale vapours 
led to the production of the world-famous refrige- 
rator — the Bell-Colernan — by which the great 
ocean trade in frozen meats has been made possible. 
An Australian Remedy.— A very simple treat- 
ment of snake bite is said to be applied by the 
natives in Australia with uniform success. A piece 
of human hair string is tied tightly three or four 
inches above the bite, a small circle an eighth of 
an inch deep is cut around the two fang punctures 
with a sharp stone knife, and the largest vein be- 
low the bite is slit to allow the blood to run out 
A stream of water is turned on the affected part, 
and the limb is rubbed down steadily for about 
twenty minutes. When every drop of blood, seems 
to have been \ >asse i out of this part of the body the 
slit vein is twitched up with a piece of sharp thin 
wood, dirt is applied to the wound, and the string 
is removed. 
Electric Heat for Plants. -For a number of 
years, experiments with the electric light and the 
electric current in forcing vegetables have attrac- 
ted considerable attention, but electric heating for 
conservatories, the idea of two Swiss electricians, 
seems to be a novelty — in practice, at least. It 
gives promise of. good results wherever, as in Swit- 
zerland, cheap motive power may be had. A dy- 
namo sends the current into receivers of special 
metallic composition, which became rapidly heated 
to a certain temperature, but not beyond, and gives 
forth the heat like steam-radiators, Important ad- 
vantages are claimed. The apparatus is very simple 
and cleanly, injurious gases are avoided, and the 
heat can be regulated at will without risk of fire 
and turned on or shut off very readily. 
Plow the Coal is Burning.— A statistician has 
attempted to determine approximately the world’s 
consumption of coal. He estimates that in gen- 
erating steam for engines aggregating 10,000,000 
horse power (some authors rate the world’s engines 
as high as 20,000,000 horse power) coal is burned 
to the amount of about 12,000 tons per hour. For 
gxs for lighting,' the consumption is not less than 
] 0,000 tons per hour; and for gas for heating and 
motive power, probably 4,500 tons. In metallurgy 
t’.ie use of coal reaches about 9,000 tons per hour; 
and in workshops and factories, 5,000 tons. It is 
difficult to calculate the quantity employed for 
domestic purposes, but 55,000 tons per hour, or 
1,320,000 tons per day of twenty-four hours, seems 
to be an underestimate. Placing the actual daily 
consumption for the entire world as low as 1,600,000 
tons, we find that a solid cube of coal more than 
100 yards on a side is burned up every day. 
A Lake of Ink: — Near the eastern end of the 
remarkable volcanic area of Arizona is a little lake 
of ink black water, ft is about a quarter of a mile 
long and half as wide, and is fed by numerous 
little streams — some hot, some warm, and one or 
two cold — whose waters are strongly charged with 
different acid and alkaline salts. The water of the 
1 lake feels smooth and oily, and its taste is salt and 
