662 



NATURE 



[July 21, 192 1 



already been carried out by several companies, but 

 owing to a variety of circumstances, largely influenced 

 by the war, operations practically ceased in that year, 

 though production has since been maintained inter- 

 mittently by a few companies. The geology of the 

 area is essentially Cretaceous, and the structures are 

 typical of the eastern foothill ranges of the Rocky 

 Mountains, consisting of sharp folds broken by p>ower- 

 ful faulting consequent on long-continued earth stress. 

 The main tectonic feature is that of the Turner Valley 

 anticline, from which the bulk of the oil and gas has 

 been obtained ; this involves the Kootenay-Dakota, 

 Benton, and Belly River series (in ascending order); 

 petroliferous horizons are principally confined to the 

 older rocks, four distinct oil-sands being recognised. 

 Water-bearing beds were not penetrated by any of 

 the wells put down, although two of these reached 

 a depth of 3900 ft. The yield of gas is as much as 

 5,000,000 cub. ft. per day in some cases, while 

 the best oil well (South Alberta Oil Co., No. i) pro- 

 duces 30 barrels per day. The gas has an average 

 composition of 70 per cent, of methane, the rest 

 being ethane and nitrogen ; the oil has a specific 

 gravity of 0736 (example from the second oil-sand), 

 and is described as a high-grade oil ; the yield of 

 petrol, however, varies considerably. As a technical 

 publication this memoir maintains the high standard 

 of excellence characteristic of Canadian official 

 literature. 



Meteorological results for 1920 at the Falmouth 

 Observatory, a station which is financially assisted by 

 the Meteorological Office, show that bright sun- 

 shine was registered for 1508 hours, or 245 hours 

 fewer than the average for the past forty years. A 

 deficiency of sunshine occurred in each month except 

 December. Bright sunshine was registered on 308 days, 

 a figure which is four days above the mean. The mean 

 temperature for the year was 5 14° F., or 07° above 

 the average. The absolute maximum for the year was 

 70- 1° F. in August, which is the lowest annual maxi- 

 mum since observations were started fifty years 

 ago. Rainfall was 208 in. above the average for 

 the last fifty years. The relative distribution of 

 the wind was in good agreement with the normal. 

 A fifty years' average, 1871-1920, is given for atmo- 

 spheric pressure, air temperature, rainfall, humidity, 

 and direction of wind for each month and for the 

 year; these add much to the valuable work which is 

 being done at the station. 



In the July issue of the Philosophical Magazine Mr. 

 E. C. Kemble, of Harvard University, reviews the 

 evidence now available for testing the various sugges- 

 tions which have been made as to the constitution of 

 the helium atom. Bohr's hypothesis that it contains 

 two electrons revolving in a common circular orbit is 

 not in keeping with the known value of the ionisation 

 potential. The models of Land^ and of Franck and 

 Reiche involve an outer and an inner electron each 

 with its own orbit. Such an outer electron would, on 

 the theories of Langmuir and of Sir Joseph Thomson, 

 determine the chemical behaviour of the atom, and it 

 would be difficult to reconcile the chemical properties of 

 helium with those of the alkali metals. These models 

 nlso give wrong values for the ionisation potential, and 

 NO. 2699, "VOL. 107] 



do not harmonise with the spectroscopic observations 

 of Fricke and Lyman. In all the models the average 

 angular momentum of an electron is taken to be an 

 integral multiple of the unit, and, according to Bohr's 

 principle, an electron on changing its orbit emits one 

 or more units of radiation. Mr. Kemble shows that 

 the principle cannot be applied in all cases without 

 leading to inconsistencies, and comes to the conclusion 

 that it must be abandoned. 



In Science for May 20 Dr. S. J. Barnett, of the 

 Terrestrial Magnetism Department of the Carnegie 

 Institution, Washington, reviews recent progress in 

 the theory of magnetism and its simplest applications. 

 He shows how the Weber-Langevin theory, according 

 to which the magnetic element contains a permanent 

 whirl of electricity with a definite magnetic moment, 

 is incapable of explaining the known facts of dia-, 

 para-, and ferro-magnetism, and that the magnetic 

 element, or magneton, must be taken as having an 

 angular velocity of its own about some axis which 

 may or may not be an axis of figure. In these cir- 

 cumstances the magneton will behave as a gyrostat, 

 and a rotation impressed on the body of which the 

 magneton forms part will tend to make the magneton 

 set its axis more in the direction of that of rotation of 

 the body, and thus impart to it a magnetisation along" 

 the axis of rotation. The gyrostatic magneton in the. 

 hands of Ganz and of Honda and Okuba has yielded 

 results which follow very closely the experimental 

 facts, the theory of Ganz covering a wide range of 

 cases, and in particular reproducing accurately the 

 behaviour of dense paramagnetic bodies at low tem- 

 peratures. 



Sir William Abnev's career as a scientific photo- 

 grapher forms the subject of a memorial lecture de- 

 livered by Mr. Chapman Jones before the Royal 

 Photographic Society, and published in the Photo- 

 graphic Journal for July. From his youth Sir William 

 Abney had more than a liking for scientific subjects, 

 but photography was his first choice. At that time the 

 spectroscope was beginning to take its proper place 

 as an instrument of investigation, and he was one of 

 the first to enter this new field and to apply the spec- 

 troscope to the elucidation of photographic problems. 

 He took advantage of the fact that the exposure effect 

 in a chromated gelatine film, if merely started by 

 light, will continue to grow, and showed how the 

 bugbear of the carbon printers could be turned to 

 useful account. In 1871, if not earlier, Abney de- 

 voted his attention to the preparation of photographic 

 emulsions and sensitive films, and later on obtained 

 results from which the modern P.O. P. originated. 

 During about twentj^-four years he investigated the 

 nature of the developable image and the course of 

 development. By 1880 he had worked out various 

 methods for printing by development. He made a 

 series of experiments on developing- agents, and intro- 

 duced the use of hydroquinone and the ferrous-citro- 

 oxalate developer, which need no restrainer. One of 

 Abnev's most important discoveries he called "the 

 failure of a photographic law." He proved that the 

 time of exposure did not vary exactly inversely to the 



