July 26, 191 7] 



NATURE 



431 



it had been largely stoneware imported from Germany. 

 Fused silica ware has to some extent been .able to 

 make good the deficiency, and has helped to equip 

 numerous factories erected in connection with the 

 supply of explosives, especially as regards apparatus 

 for the concentration of sulphuric acid and the con- 

 densation of nitric acid. Dr. F. Bottomley gives de- 

 tails of plants fitted with fused silica condensers, 

 evaporators, etc., for these two acids, in the Journal 

 of the Society of Chemical Industry for June 15, and 

 also outlines the progress which has been made in the 

 production of fused silica apparatus generally. Sixteen 

 years ago small articles of silica were made by labo- 

 riously fusing quartz a few grains at a time in the 

 oxyhydrogen blowpipe flame ; at the present day the 

 weight of fused material which can be worked exceeds 

 200 lb. The temperature required is between 1800° 

 and 2000° C. In the plastic condition the silica is very 

 ductile, and can be drawn out like glass in lengths 

 of 90 to 100 ft. 



Tech.nologic Papers Nos. 83 and 84 of the U.S. 

 Bureau of Standards represent continuations of Merica 

 and Woodward's work on the " Failure of Brass " 

 (No. 82). In the former an account is given of the 

 study of the effect of tensile stress on the electrolytic 

 solution potential of brass to various solutions, the 

 results indicating an increase of E.M.F. of about o-i 

 millivolt per 10,000 lb. /sq. in. of stress. An explana- 

 tion is given, based upon this effect, of the decreased 

 ductility and strength exhibited by brass, w'here 

 corroded while under tensile stress, and describes the 

 growth of fissures in brass under such conditions. 

 In the latter the results are recorded of an investiga- 

 tion of the initial stresses produced by the burning-in. 

 without pre-heating, of constrained parts of castings of 

 manganese bronze. Results have shown that, in 

 general, tensile stresses will be produced within the 

 burned-in area equal in value to the true elastic limit 

 of the material. The conclusion is drawn that bum- 

 Ing-in of such material should not be practised without 

 thorough pre-heating or subsequent annealing of the 

 whole casting. 



The Biochemical Journal for May contains a paper 

 by Mr. H. E. .\nnett describing the isolation of 

 raffinose from the seed of the jute plant {Corchorus 

 capsularis). The sugar was identified by its content 

 of w-ater of crystallisation, specific rotatory power, 

 and the change of the latter when the sugar was 

 acted upon with emulsin, invertase, and melibiase. 

 Further, the sugar does not give an osazone, but 

 from the products of its hydrolysis with invertase, 

 glucosazone and galactosazone were isolated. The 

 sugar was isolated by extracting the finely ground 

 jute seed, which had previously been exhausted with 

 ether and petrol, with alcohol,' and precipitating the 

 alcoholic extract with ether. The particular sample 

 of seed examined contained 225 per cent, of raffinose. 



Op- the chemical changes induced in amino-acids by 



bacterial action, the most common and the one that 



has been most studied is simple decarboxylation. It 



IS by this process that putrescine and cadaverine are 



formed in the putrefaction of ornithine and Ij'sine 



I respectively. The deaminisation {i.e. loss of 



I ammonia) of amino-acids by bacteria is usually ac- 



j -companied by reduction, e.g. in the production of 



^hydro.xyphenyl-propionic acid from tyrosine. Mr. 



I H. Raistrick, however, in the Biochemical Journal 



I for May, describes the formation of an unsaturated 



. carboxylic acid by the action of bacteria on histidine. 



I This author avoided any possible secondarv re- 



i actions by arranging that the histidine was the only 



organic substance present in the rnedium on which 



the bacteria were cultivated. When B. cdZI co»n- 



XO. 2491, VOL. 99] ' 



munis. B. typhosus, B. paratyphosus A, B. paraty- 

 ■phosus B, B» enteritidis, Gaertner, or B. dysen- 

 teriae, Flexner, is grown on a medium consisting of 

 Ringer's solution + histidine (fl-iminazolyl-o-amino- 

 propionic acid), from 5 to 60 per cent, of urocanic 

 acid (yS-iminazolylacrjlic acid) is formed, the largest 

 proportion with B. paratyphosus A, and the smallest 

 with jB. typhosus. The acid was identified by analysis, 

 melting point, and preparation of the picrate and 

 nitrate. This is the first instance on record of the 

 bacteriological conversion of an amino-acid into an 

 unsaturated acid. 



Mr. John Murray's list of announcements for the 

 coming autumn contains several works which should be 

 of interest to readers of Nature, e.g. "The Life and 

 Letters of Sir J. D. Hooker, O.M., G.C.S.I.," by 

 Leonard Huxley, two vols. ; "The Life of Sir Clements 

 Markham, K.C.B., F.R.S.,' by Admiral Sir A. H. 

 Markham; "The Life of Sir Colin C. Scott Moncrieff," 

 edited by Miss M. A.' HoUings; "Rustic Sounds and 

 other Studies in Literature and Natural History," by 

 Sir Francis Darwin; "Volcanic Studies in Many 

 Lands," by the late Dr. Tempest .Anderson; second 

 series, "Cotton and other Vegetable Fibres," by Dr. E. 

 Goulding (Imperial Institute Handbooks), and a new 

 and revised edition of "The Book of the Rothamsted 

 Experiments," edited by Dr. E. J. Russell. 



Messrs. J. Wheldon and Co., 38 Great Queen 

 Street, Kingsway, have just issued a catalogue 

 (New Series, No. 80) of books and papers on chem- 

 istry, pure and applied, mineralogy-, mining, and 

 geology. The list contains many works published in 

 enemy countries and therefore difficult to obtain new 

 at the present time; also the modern library of Mr. 

 Andrea Angel, who lost his life in the East End 

 explosion in January last. The catalogue will be sent 

 free upon application. 



OUR ASTRONOMICAL COLUMN. 

 Meteors on July 19. — Though meteors were singu- 

 larly rare in the two hours before midnight on July 19 

 they were rather abundant and brilliant after mid- 

 night. .\t i2h. 12m. G.M.T. one of magnitude i shot 

 rapidly from 339° + 720 to 261^ + 41°, and left a bright 

 streak. Its radiant was probably between a and j8 

 Persei. At i2h. i8m. a meteor exceeding magnitude i 

 passed from 320° + 35° to 317° + 27°, and was directed 

 from Cepheus. At i2h. 37m. a ven,- fine meteor with 

 an extraordinarily long course of 89° travelled slowly 

 from 328°+ 11° to 238° 4- 10°, and left a bright streak 

 in its wake. At I3h. 35m. a blue, flashing meteor 

 shot rapidly down across the star 7] Pegasi, and was 

 directed from a shower near o Cygni or at 3 16° 4- 48°. At 

 i3h. 50m. a tolerably bright meteor, leaving a streak, 

 crossed the cluster in Perseus from a radiant at 

 40° 4- 20°, and at i4h. 15m. a bright Perseid, leaving 

 a streak, shot from 326^° 4- 17^ to 316° 4-6°. Dupli- 

 cate observations of any of these interesting objects, if 

 sent to Mr. \\\ F. Denning (44 Egerton Road, Bris- 

 tol) would enable their heights, etc., to be computed. 



Annuario of the Rio de Janeiro Observ.atory. — 

 The thirty-third issue of this useful publication has re- 

 cently been received. It contains numerous ephemerides 

 and other astronomical data, together with an excellent 

 collection of tables for the reduction of astronomical 

 observations. A section is devoted to terrestrial 

 physics, with special reference to the magnetic elements 

 and the intensitv of gravity, and another includes 

 details of meteorological obseWations made at twenty- 

 five stations in Brazil. Tide-tables for seven Brazilian 

 ports, calculated with the aid of the Kelvin tide- 

 predictor, are afso included in the volume. 



