December 9, 1920] 



NATURE 



475 



tion of the Mackenzie River covers a very large 

 area, extending for hundreds of miles along the 

 direction of the river. In the reported words of 

 a geologist who accompanied the drilling party 

 this year, " the biggest oilfield in the world is 

 what has now been op>ened in the north." 



Before this great oilfield can be made com- 

 mercially profitable there are, of course, many 

 difficulties to contend with, especially the long 

 distance from civilisation, the severity of the 

 Arctic climate, and the lack of adequate trans- 

 portation. But as these obstacles did not prevent 

 the exploitation of the gold in Klondike, we need 

 have little fear but that this precious fluid in the 

 Mackenzie valley will be won. 



Several of the Canadian Geological Survey 

 Memoirs describe the Mackenzie River district, 

 though they do not enlighten us much on the 

 subject of petroleum, which was the special object 

 of the Bosworth expedition. The most interesting 



of these is the report by Mr. R. G. McConnell, 

 published in 1891, which mentions the bituminous 

 rocks and pools of tar and oil, which he observed 

 in many places. Memoir 108, on "The Mackenzie 

 River Basin," by Messrs. Charles Camsell and 

 Wyatt Malcolm, which appeared in 1919, also 

 cites particularly the oil indications which Mr. 

 McConnell had found, some of which had been 

 noticed also by Sir John' Franklin a century ago. 

 This official memoir is very guarded on the 

 subject of petroleum, and does not afford great 

 encouragement to oil prospecting on the Mac- 

 kenzie ; but it is a comprehensive summary of 

 the previously established facts, together with 

 many valuable observations, old and new. 



During the next few months there can be little 

 or no progress made with the development in this 

 frozen land, but doubtless many preparations are 

 afoot, and next spring will see an unprecedented 

 migration of oilmen to this northern clime. 



Industrial Research Associations. 



V. — The British Portland Cement Research Association. 



By S. G. S. Panisset. 



A LTHOL GH the Portland cement industry had 

 **• its origin in this country, the chief develop- 

 ments have occurred elsewhere, and the greater 

 part of the manufacturing plant now in use is 

 either of foreign production or a close copy 

 thereof. 



It may be disputed that this position has arisen 

 from the absence of organised research in this 

 >untry, but it is certainly true that the amount 

 ol scientific investigation in the British Portland 

 cement industry has been insignificant compared 

 with the work done in the United States and on 

 the Continent. 



With these circumstances existing, it is clear 

 that the British Portland Cement Research Asso- 

 ciation is a needed institution, and it is some 

 comfort to know that its arrival is not too late 

 !■) be effective. The extent of the field of research 

 ^'111 awaiting exploration is such that no agreed 



iswer can be given to the fundamental ques- 

 lions, "What is Portland cement?" and "What 

 happens when cement sets? " 



In spite of the extensive research that has been 



■ nducted in the United States by Government 

 institutions and by universities, the real nature 

 of cement, and the chemistry and mechanism of 

 its setting, are still matters of controversy, owing 

 to the lack of concrete evidence. 



The manufacture, in fact, is still in the em- 

 pirical stage, ba.sed solely upon the knowledge 

 that a mixture of calcareous and argillaceous 

 materials containing about 76 per cent, of car- 

 bonate of lime will, when heated to incipient vitrc- 

 faction, yield a product which on grinding has 

 pronounced hydraulic properties. Whether the 

 hydraulic effect is due to the presence of simple 

 silicates and aluminates of lime, whether complex 

 NO. 2667, VOL. 106] 



ternary comjwunds exist, or whether a part of the 

 lime is uncombined and in the state of solid solu- 

 tion, are all problems which must be solved before 

 it can be claimed that the best possible con- 

 structional material is being produced. 



In connection with the setting of cement, it is 

 still undecided whether this is due to colloidal 

 or to crystalline action, and the manufacturer is 

 accordingly in the dark as to whether he ought to 

 be aiming at the production of colloids or of 

 crystalline bodies to produce the best results. 



The composure of manufacturers has now and 

 again been disturbed by predictions that cement 

 can be made from a mixture containing only two- 

 thirds the conventional proportion of lime, and 

 again that the stage of incipient vitrefaction now 

 produced in rotary kilns can be improved upon 

 by adopting blast-furnace methods and carrying 

 the temperature to melting point. From the 

 point of view of scientific knowledge the manufac- 

 turer is unable to deny that such statements arc 

 within the range of possibility, and hence there is 

 always the fear that more than half the present 

 cement-making plant may be rendered obsolete 

 by new discoveries. 



This is not a happy position for an industry, 

 especially when such a discovery is likely 

 to be the property of those who have hitherto 

 been foremost in research — namely, the foreign 

 competitor — and in this connection the advent of 

 the British Portland Cement Research Associa- 

 tion is not a day too soon. 



Again, if it be supposed that the present 

 methods of manufacture arc permanent, the fact 

 has to be faced that the thermal efficiency of the 

 kilns in use is seldom more than 50 per rent., 

 and here is a field for research that may lead, 



