1921 .] 
Reviews and Abstracts. 
143 
the overthrust of the Harz, while the relative proportions of both ranges 
are approximately the same. 
As regards the direction of the folding force, 44 Marshall and Morgan 
express themselves clearly for a thrust from the east ; Suess assumes 
that the compression came from the west; Park’s representation can be 
explained in different senses.” The general trend of the argument seems 
to favour pressure from the east, that side being therefore the inner side, 
to the fracture and depression of which the eruptive masses of Banks and 
Otago Peninsulas owe their origin. Great fractures are also assumed for 
the outside, so that much of the folded mountains should lie under the 
Tasman Sea. On the other hand, the western dip of the dislocation-planes 
of the Moonlight and Kaikoura overthrusts does not agree well with the 
supposition that the inner side of the mountains lies in the east. These 
overthrusts show that strong mountain-building movements occurred during 
the younger Tertiary. 
New Zealand can perhaps be classed as a region of Mesozoic geosynclines 
and of Tertiary mountain-chains. The strong folding in the Tertiary of 
the Puketoi Hills mentioned by Marshall is perhaps of importance for fixing 
the time of the mountain-building. J. M. 
Fuel for Motor Transport. — An interim memorandum by the Fuel 
Research Board, Department of Scientific and Industrial Research, 
London, July, 1920. 
The threatened shortage of motor-fuel oil is forcing this question into 
prominence, and the Fuel Research Board of Great Britain is dealing with 
the question. This memorandum discusses the question of power-alcohol, 
and points out that on a very large scale it can only be made by diverting 
foodstuffs or land suitable for the growth of foodstuffs, and that it will be 
better, therefore, to develop the recovery of motor-fuel oils from coal to 
its utmost limit before seeking to substitute power-alcohol. The position 
is summarized in the report as follows 
(1.) Coal is the largest as well as the cheapest source of fuels for 
transport purposes. 
(2.) Means are already in our hands for the 44 sorting-out ” of the 
potential energy of coal into forms of different availability and of different 
commercial value. 
(3.) The more volatile forms like benzol and light naphtha are so rela¬ 
tively costly that they ought only to be used for air transport, or for the 
lighter and swifter forms of road transport. Their use for the heavier 
forms of transport is wasteful and unnecessary. 
(4.) Town gas and coke-oven gas are available in large quantities in 
most parts of the country, and might be extensively used in omnibuses 
and passenger-cars for quick traffic, if light and yet safe containers could 
be constructed, and if stations were established on the principal routes at 
which the containers could be quickly and easily replenished. If carbon¬ 
ization of coal at temperatures about 600° C. becomes common, gas of twice 
the calorific value of town gas would be available for this purpose, so that 
twice the thermal units could be carried in the same containers. 
(5.) The coke produced by the carbonization of coal at 600° C. is a 
tarless, smokeless fuel, easily lighted and easily kept alight, and would be 
admirably adapted for use in suction-gas producers and engines. The cost 
of the thermal units produced in this way would not exceed 3s. per million, 
or one-seventh of the cost of petrol units with petrol at 3s. per gallon. 
L. B. 
