NOTES 653 



mentally (1) in their manner of origin, (2) in their relation to the structure 

 of the organism, (3) in their relation to recapitulation, adaptation, and in- 

 heritance, (4) in relation to geographic distribution. To the first category 

 belong cell-characters, which arise as mutations, and are usually inherited 

 as distinct entities, and, being borne by the nuclei, may be called " Karyo- 

 genic " characters. To the second category belong organismal characters 

 which arise gradually through impact with the environment or through 

 orthogenic changes, may modify localised parts of the life-cycle, and may 

 not be incorporated in the germ-plasm from the first. 



Dr. F. W. Aston, in a letter to Nature (December 18, 1919), gives a pre- 

 liminary account of some of the results he has obtained with an improved 

 positive-ray spectrograph. He finds that carbon and oxygen show no signs 

 of possessing isotopic forms ; that chlorine consists of two isotopes of atomic 

 weights 35 and 37 ; that neon, as is well known, is a mixture of two, whose 

 atomic weights are 20 and 22 (correct to a tenth of 1 per cent.) ; while mer- 

 cury is a mixture of at least three or four. Experiments giving more than 

 forty different values of atomic and molecular mass show that all are exact 

 integers (taking C = 12 and O = 16). The case of hydrogen, which clearly 

 becomes of special interest if these results are confirmed, has not yet been 

 investigated. 



Quite the most interesting exhibit at the Physical and Optical Societies 

 Joint Exhibition, which was held at the Imperial College of Science on 

 January 7 and 8, was the Sheringham Daylight device. This invention is 

 one of the simple why-didn't-I-think-of-it-before type, which should be of 

 material assistance in the colour industries. It consists merely of a large 

 umbrella-shaped reflector placed above a high-candle-power electric lamp, 

 the reflecting surface being covered with small squares of coloured paper 

 arranged in chessboard fashion. These squares are of many different 

 colours, blues and greens predominating, so that the excess of yellow in the 

 artificial light is eliminated. The energy wave-length curve of the light 

 diffused from the reflector can be plotted from measurements obtained with 

 a spectro-photometer, and thus the proportions of the different colours on 

 the reflector can be adjusted to match any desired quality of daylight with 

 any specified source of illumination. The usefulness of the new illuminator 

 in the dye trade, in drapery stores, in the lighting of art galleries, etc., is 

 self-obvious, and it will make it possible to specify a standard " daylight " 

 in which all colour-matching processes may be carried out. 



The Bureau of Standards, Washington, has just issued a revised list of 

 its various publications (Circular No. 24). Since the first paper was printed 

 in 1904, the staff of the Bureau has been responsible for 338 papers of purely 

 scientific interest, 138 technical papers, and 82 circulars. Among the latest 

 of these is a paper by Coblentz and Kahler dealing with the optical and 

 photo-electric properties of Molybdenite, which is conspicuous for its high 

 photo-electric sensitivity to infra-red rays extending to 3 n ; a paper dealing 

 with the effects of glucose and salts on the wearing qualities of sole leather, 

 and the first of a series of investigations intended to establish, by laboratory 

 methods, the relative values of different deposits of stone for building pur- 

 poses. The whole of these publications (with the exception of a very few 

 now out of print) can be obtained from the Bureau at a small cost which 

 varies with the length of the paper. 



The Report on Engineering Standardisation written by Mr. Gerald Light- 

 foot for the Australian Institute of Science and Industry rather startles us at 

 the outset by holding up Great Britain, along with the United States, as an 

 example of a country where standardisation in the engineering industry 

 has reached a high stage of development. Nevertheless, on reading further 

 through his pages we are able to realise that, as compared with Australia, 

 the conditions in this country form an ideal to be striven after. It appears 



