562 Notices of Memoirs—Professor W. S. Boulton— 
(including Egypt) produced only a little more than 2 per cent. In 
the near future Canada is likely to take its place as a great oil- and 
gas-producing country, for large areas in the middle-west show 
promising indications of a greatly increased yield. But Mexico is 
undoubtedly the country of greatest potential output. Its Cretaceous 
and Tertiary strata along the Gulf Coastal Plain are so rich that 
it has been stated recently on high authority that ‘‘ a dozen wells in 
Mexico, if opened to their full capacity, could almost double the 
daily output of the world’’. 
As is well known, natural supplies of petroleum are not found in 
the British Isles on a commercial scale; but for many years oil and 
other valuable products have been obtained from the destructive 
distillation of the oil shales of the Lothians. If Mr. Cunningham 
Craig is right in his views recently expressed,* these shales, or 
rather, their associated freestones, have been nearer to being true 
petroliferous rocks than we thought; for he believes that the small 
yellow bodies, the so-called ‘spores’ in the kerogen shales, are really. 
small masses of inspissated petroleum absorbed from the porous. — 
and once petroliferous sandstones with which the shales are 
interstratified. 
If recent experiments on peat fulfil the promise they undoubtedly 
show, we shall have to take careful stock of the peat-bogs in these 
Islands. It is well known that peat fuel has been manufactured in 
Europe for many years. But my attention has been called to 
a process for the extraction of fuel-oil from peat, which has been 
tried experimentally in London, and is now about to be launched on 
a commercial scale, utilizing our own peat deposits, like those of 
Lanarkshire and Yorkshire... . 
It is sometimes asked whether the adoption of mineral oil as 
a power-producer is likely to supplant coal, and thereby seriously 
reduce the output of that mineral. The world’s yield of petroleum 
will doubtless go on increasing at a very great rate; but from the 
experience gained in some of the fields in the United States and 
Eastern Canada, it seems unlikely that this increase can continue 
for a very long period. Practically complete exhaustion of the 
world’s supply is to be looked for within 100 years, says one 
authority.2 Even if the output rose to ten times the present yield, 
it would represent only about half the present world output of coal, 
and it is practically certain that so high a yield of oil could not be 
maintained for many years. Owing to the almost certain rapid 
increase in the output of coal, estimates made by the same authority 
already quoted indicate that the total production of petroleum could 
never reduce the world’s output of coal by more than about 
64 per cent.* 
For us, and probably for those of the next generation, the geology 
1 Ralph Arnold, ‘‘Conservation of the Oil and Gas Resources of the 
Americas’’: Econ. Geol., vol. xi, No. 3, p. 222, 1916. 
2 Institution of Petroleum Technologists, April, 1916. 
3 H. S. Jevons, British Coal Trade, 1915, p. 710. 
+ Thid., p. 716. 
