PRESIDENTIAL ADDRESS. 389 



first International Coal Census, the ' Report on the Coal Resources of the 

 World," it would appear that we might reasonably link the Cretaceo-Tertiary 

 Period with the Carboniferous in respect of these peculiar and widely prevalent 

 coal-making conditions. For I find that of the actual and probable reserves of 

 coal in the world, according to our present state of knowledge, about ig mil- 

 lion million tons of bituminous and anthracite coal exist, the vast bulk of 

 which is of Carboniferous age ; while there are about 3 million million tons of 

 lignites and sub-bituminous coals, mostly of Cretaceous and Tertiary age. 



When we look to the geological distribution of Petroleum, we note that it is 

 to be found in rocks of practically eveiy age in more or less quantity, but that 

 it occurs par excellence, and on a great commercial scale, in rocks of two 

 geological periods (to a smaller extent in, a third) ; and it is significant that 

 these two periods are the great coal-making periods in geological history — the 

 Carboniferous and the Cretaceo-Tertiary. It would take me beyond my present 

 purpose to explore the avenues of thought and speculation opened up by this 

 parallel. I will only remark that it seems to afford some support for the view 

 that coal and petroleum are genetically as well as chemically related. While the 

 terrestrial vegetation of tlie two periods was accumulating under specially 

 favourable physiographical conditions ultimately to be mineralised into seams of 

 coal, the stores of petroleum believed to be indigenous to strata of the same 

 periods were probably derived from the natural distillation of the plankton 

 which must have flourished, too, on an enormous scale in the shallow, muddy 

 waters adjacent to this luxuriant land growth. The phytoplankton, including 

 such families as the Diatomaceaj and Peridinise, may well have played the 

 chief role in this petroleum formation, w-liile affording unlimited sustenance 

 to the small and lowly animal organisms, like Entomostraca, whose fatty 

 distillates doubtless contributed to the stores of oil. It is possible, then, that 

 a prodigious development of a new and vigorous flora during both periods — 

 the spore-beai'ing flora, in the main, of the Carboniferous, and the seed-bearing 

 flora of the Cretaceo-Tertiary period — was the chief contributory factor in the 

 making of the world's vast store of solid and liquid fuel. It contributed 

 directly by supplying the vegetable matter for the coal, and inddrectly by 

 stimulating the development of a prolific plankton, from which the oil has been 

 distilled. 



The world's production of petroleum has trebled itself within the last fifteen 

 years. In 1914 the United States of Aimerica produced 6636 per cent., and 

 North and South America together nearly three-fourths of the world's total 

 yield ; while the British Empire (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.' "^ 



Als 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 sand- 

 stones 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 



" Report on ' The Coal Resources of the World ' for the Twelfth Intern. 

 Geol. Congress, 1913. 



" Ralph Arnold, ' Conservation of the Oil and Gas Resources of the 

 Americas,' Econ. OenL, vol. xi., No. 3, 1916, p. 222. 



^* Institution of Petroleum Technologists, April 1916. 



