i8 



NA rURE 



[November 3, 1892 



Berlin, It may be remembered that in our note of a fortnight 

 ago (vol. 46, p. 596), it was announced that Prof. Emil Fischer 

 and Dr. Landsteiner had succeeded for the first time in pre- 

 paring this interesting substance in a state of tolerable purity by 

 a reaction analogous to that of barium hydrate upon acrolein 

 dibromide, the reaction which yielded the first synthetical glu- 

 cose. They first prepared the mono-bromine, derivative of common 

 aldehyde, ClIgBr.CHO, and subsequently reacted upon this new 

 substance, a liquid possessing an intolerably sharp odour, with 

 baryta water. After removal of the baryta by sulphuric acid, 

 and the hydrobromic and sulphuric acids by means of carbonate 

 of lead, a liquid was obtained which possessed the properties of 

 a dilute solution of glycol aldehyde. Some time ago Pinner 

 obtained a derivative of this aldehyde which bore the same rela- 

 tion to glycol aldehyde, that the compound known as acetal, 



qHgXH 



OC2H5 



ocjh; 



bears to common aldehyde. This substance. 



r/ 



OC2H5 



glycol acetal, CHjOH-CH/ , Pinner attempted to de- 



compose, by the action of mineral acids, into ethyl alcohol- 

 ^iid glycol aldehyde. The attempt, however, did not succeed, 

 inasmuch as the decomposition Went further, any glycol alde- 

 hyde that may have been formed during the first stage of the 

 reaction being subsequently broken up. Drs. Marckwald and 

 Ellinger now find that the reaction succeeds admirably, pro- 

 vided the acid employed is extremely dilute, and as glycol 

 acetal is a substance very easily prepared, they show that the 

 reaction affords a very convenient and advantageous method 

 of preparing large quantities of glycol aldehyde. The glycol 

 acetal is added to an equal volume of water acidified with only 

 a few drops of sulphuric acid. The liquid is then heated to 

 boiling. After a short time the two liquids mix, and the reaction 

 is completed when upon the addition of water to a few drops 

 of it no separation of oil occurs. Upon distilling the liquid 

 product, alcohol first passes over, then there distils a mixture 

 of water and glycol aldehyde until decomposition of the residue 

 commences. Glycol aldehyde, as thus obtained in a tolerably 

 concentrated form, appears to be much more volatile in steam 

 than was observed by Prof. Fischer and Dr. Landsteiner, in 

 case of their more dilute solutions. From a few cubic centi- 

 metres of the distillate Drs. Marckwald and Ellinger obtained 

 a very considerable quantity of Prof. Fischer's phenylhydrazine 

 compound, and confirm in every detail the other properties of 

 glycol aldehyde described in our previous note above referred 

 to. The chemistry of this first member of the series which in- 

 cludes the sugars is now, therefore, fairly complete, and the 

 difficulties in the way of its preparation surmounted. 



The additions to the Zoological Society's Gardens during the 

 past week include a Rhesus Monkey {Macacus rhesus i ) from 

 India, presented by Mr. Pascoe Grenfell, F.Z. S. ; a 

 Philantomba Antelope {Cephalophus maxiuelli) from West 

 A'frica ; three Gambian Pouched KdXs {Cricetomys gambianus) 

 from West Africa ; a Ground Rat {Aulacodus swindcrnianus) 

 from West Africa ; and aWhite-faced Tree Duck {Dendrocygna 

 viduata) from West Africa, presented by Mr. C. B. Mitford ; 

 a Martial Hawk-Eagle {Spizaetus bellicosus) from South Africa, 

 presented by Mr. T. White ; two Weaver Birds {ffyphatitornis 

 sp. inc.) from South Africa, presented by Mr. A. W. Arrow- 

 smith ; two Silver Pheasants (£i///(7ca/«/« nydhemerus <J i) 

 from China, presented by Mr. E. Mitchener ; a Common 

 Chameleon {Chamccleon vulgaris) from North Africa, presented 

 by Miss Kate Higgins ; a Thick-tailed Opossum {Didelphys 

 crassicaudata) from South America ; a Garden's Night- Heron 

 {Nycticorax gardeni) ; and two Saracura Rails {Aramides 

 saraaira) from South America, purchased ; and a Squirrel 

 Monkey {Chrysothrix sciurea) from Gtiiana, deposited. 

 NO. 1 20T, VOL. /\']~\ 



OUR ASTRONOMICAL COLUMN. 



Comet Brooks (August 28).— The following ephemeris, 

 which we take from Astronomische Nachrichten, No. 3125, 

 gives the apparent Right Ascensions and Declinations of Comet 

 Brooks, which is brightening very rapidly : — 



1 1 -60 



0-2298 ... 0-1539 ... i-oo 



0-2278 



[590 ... 099 



13-51 



Lying in the extreme northern corner of the constellation of 

 Sextans, and nearly midway between p Leonis and e Hydrse, 

 it will not be an easy object for observation owing to its very 

 late rising. 



Comet Barnard (October 12).— Prof. R. Schorr, of 

 Hamburg, communicates to Astronomische Nachrichten^ No. 

 3125, the elements and ephemeris of Comet Barnard, deduced 

 from observations made on October 16, 18, and 20, at Vienna, 

 Hamburg, and Pulkowa respectively. As this ephemeris differs 

 rather considerably from the one we gave last week, the follow- 

 ing places may prove of service to observers : — 



12/i. Berlin M.T. 

 „ R.A. Decl. Log>. Log A. Br. 



"^9^- h. m. s. o , 



Nov. 3 ... 20 24 38 ... -i-5 3-7 



4 ... 27 20 ... 4 440 



5 ... 30 4 ... 4 24-6 



6 ... 32 48 ... 4 5-4 



7 - 35 34 - 3 46-4 



8 ... 38 21 ... 3 278 



9 ••• 41 9 ••• 3 9'4 

 10 ... 43 58 ... 2 51-2 



This comet will still be found to form approximately an equilateral 

 triangle with a Aquilae and /S^Delphini on November 5. 



Tabular History of Astronomy to the Year 

 1500 a.d. — Dr. Felix Miiller, of Berlin, has just completed a 

 small volume entitled " Zeittafeln zur Geschichte der Mathe- 

 mathik, Phisik und Astronomic bis zum Jahre 1500," which 

 will be welcomed by all interested in the very early history of 

 the exact sciences. The book is arranged chronologically and 

 gives a short account of the chief workers in these branches of 

 science up to the year 1500. At the end of each reference a 

 list of the literature likely to be needed is added. The work is 

 published by Messrs. B. G. Teubner, Leipzig. 



A Large Telescope. — The Americans seem to have made 

 up their minds to be the possessors of the largest telescopes in 

 existence, for in spite of their owning the great Lick Refractor 

 (36-inch) we hear now that the University of Chicago are about 

 to have " the largest and most powerfultelescope in the world." 

 This instrument will be the gift of Mr. Charles Jerkes, and will 

 cost half a million dollars. The object-glass will have a diameter 

 of 45 inches and will be made by Messrs. Alvan Clark, of 

 Cambridge, Mass. 



The Atmospheres of Planets.— Of all the planets, that 

 revolve round our sun, Jupiter affords the most suitable of them 

 for the study of atmospheric circulation. That his circulation 

 will not be exactly like ours will be at once evident, for not only 

 does the sun pour his rays on his vast surface, but he possesses 

 himself heat, as is suggested by the rapid changes which these 

 cloud masses undergo. A recent hypothesis, explaining the 

 various movements in this planet's atmosphere, has been put 

 forward by Mr. Marsden Manson, in the fifth number (vol. ix.) 

 of the " Transactions of the Technical Society of the Pacific 

 Coast," San Francisco. The chief element which produces 

 these movements is the action of the sun, and it is on this reason- 

 ing that he attempts to unravel the laws underlying the circu- 

 lation in Jupiter's atmosphere. In this pamphlet he first brings 

 together spme of the facts relating to our own wind system, 

 which are generally conceded, together with the important 

 results that were gathered from the path taken by the Krakatoa 



