I30 



NATURE 



[September 22, 1921 



A MEMORANDUM has been issued under the direction 

 of. the Indian Government by Dr. Gilbert T. Walker, 

 Director-General of Indian Observatories, on the rain- 

 fall of June and July and the probable amount during 

 August and September, 1921. The monsoon appeared 

 over the various parts of the country at about the 

 normal times. The combined rainfall of June and 

 July over the plains of India as a whole is said to 

 have been nearly normal, the deficiency being only 

 I in., or 5 per cent., but there was a deficiency of 

 more than 20 per cent, in the United Provinces West, 

 the Punjab east and north, the North-West Frontier 

 Province, Baluchistan, Central India East, and Mala- 

 bar. The memorandum gives the actual rainfall for 

 the separate months June and July and the departure 

 from the normal for the fifteen chief political divisions 

 and the thirty-three sub-divisions of India. Details 

 are given of the recent data regarding the conditions 

 most likely to have influence on the rains of August 

 and September, 192 1 ; atmospheric pressure over India 

 and the snowfall in mountain regions, as well as the 

 meteorological conditions over the Indian Ocean and 

 in other parts are discussed. From these condi- 

 tions it is summarised that in North-West India, 

 including the west of the United Provinces, and in the 

 Peninsula, it is likely that the total rainfall of August 

 and September will exceed the average. For North- 

 East India and Burma the conditions are said to be 

 too uncertain to justify a forecast. 



About five years ago Prof. Omori made some in- 

 teresting seismometric measurements of the move- 

 ments of the great chimney at Saganoseki under the 

 action of wind (Nature, vol. loi, 1918, p. 436). It 

 was found that the top of this chimney, 550 ft. in 

 height, moved through a total range of 7I in. when 

 the velocity of the wind was 78 miles an hour. The 

 most interesting result of the measurements was that 

 this movement took place at right angles to the 

 direction of the wind. With the wind the range was 

 always under i in. Prof. Omori has recentlv re- 

 peated these experiments on other columns (Bull. 

 Imp. Earthq. Inv. Com., vol. 9, 192 1, pp. 77-152). 

 The most lofty is the reinforced concrete tower of 

 the new wireless telegraph station of Haranomachi. 

 This is a hollow, truncated cone, 660 ft. in height, 

 with an external diameter of 57 ft. 9 in. at the base, 

 and of 4 ft. 6 in. at the top, the thickness of the con- 

 crete wall being 33 in. and 6 in. resi)ectively. The 

 tower is situated about 200 km. from the principal 

 earthquake zone off the east coast of Japan. The move- 

 ments were registered by a portable two-component 

 tremor-recorder magnifying from 10 to 30 times. 

 Experiments were made at various times during the 

 construction and after the completion of the tower, 

 the maximum velocity of the wind varying from 20 

 to 45 miles an hour. It was found that the move- 

 ments were quite insignificant until the height of 

 the column was 290 ft., and they became distinct only 

 when the height exceeded 5.00 ft. On com- 

 pletion, the maximum range (or double amplitude) 

 was 69 mm., but this was increased to above 103 mm. 

 when the iron frame, weighing more than two tons, 

 was attached just below the top. The range of 

 6-9 mm. was attained in the direction perpendicular 

 NO. 2708, VOL. 108] 



to that of the wind. With the wind the maximum 

 range was only 19 mm. The period of vibration of 

 the completed column was 207 seconds, or 2- 12 

 seconds after the addition of the iron frame. Prof. 

 Omori has also measured the vibrations of a twelve- 

 story brick tower, 172 ft. high, at Tokyo, and 01 

 six five-stoni- Buddhist pagodas in various parts of 

 the country. 



At the Washington meeting of the American 

 Physical Society in April last Prof. W. F. G. Swann, 

 of the University of Minnesota, directed attention 

 to the influence of the size of the earth on certain 

 changes in terrestrial magnetism. The method of 

 investigation is not exact from the mathematical 

 point of view, but keeps the physical principles in- 

 volved in the calculation clearly to the fore. In the 

 first place, it is shown that electric currents once 

 started in a copper sphere of the size of the earth 

 would decrease to 37 per cent, of their initial value in 

 3,000,000 years. In the second, that if such a sphere 

 were originally magnetised and means were then 

 taken to demagnetise it, the same statement would 

 hold for the magnetism. In the third place, if the 

 so-called secular variation of the magnetisation be 

 regarded as due to the rotation about the earth's axis 

 once in 500 years of a uniform magnetisation per- 

 pendicular to that axis, the interior conductivity of 

 the earth must be of the order 1/30,000 of that of 

 copjjer. In the short paper in the issue of the Journal 

 of the Washington Academy of Sciences for June 19, 

 which is the only account of Prof. Swann 's con- 

 clusions at present available, he points out that corre- 

 sponding statements may be made with respect to 

 the sun. 



With reference to the inquiries made by Mr. Hedger 

 Wallace in a letter entitled " Cornalith " published in 

 Nature of .\ugust 25, p. 811, we learn from Messrs. 

 Erinoid, Ltd., of Lightpill Mills, Stroud, Gloucester, 

 that cornalith and galalith are both trade names used 

 bv different firms for ivory and horn substitutes, etc. 

 Galalith is the trade name for a casein-formaldehyde 

 material manufactured by the Galalith Co. of Ger- 

 manv ; cornalith is presumably the name selected 

 bv one particular firm to indicate that imitations of 

 horn are their chief products. In England casein- 

 formaldehyde products are manufactured and sold as 

 raw material under the name of "erinoid," and 

 Messrs. Erinoid, Ltd., claim that their output, nearly 

 700 tons, during the past year is far in excess of the 

 combined output of both galalith and cornalith fac- 

 tories. The firm exhibited some of their products at 

 the British Scientific Products Exhibitions organised 

 in 1918 under the auspices of the British Science 

 Guild. Vegetable casein has not so far proved as 

 suitable as milk casein for the manufacture of casein- 

 formaldehyde material, but if the Galalith Co. chose 

 to send out. an inferior product made from vegetable 

 casein, there is nothing to prevent them from apply- 

 ing to it their own trade-name "galalith." 



Messrs. Charles Baker, of 244 High Holborn, 

 W.C.I, have issued recently a new classified list (No. 

 73) of second-hand scientific instruments and books. 

 The catalogue contains a number of microscopes, of 



