November 8, i 894J 



NATURE 



Messrs. K. and J. Beck have just issued an illustrated 

 catalogue of microscopes, object-glasses, and other apparatus 

 for which they are famed. In it we find descriptions of micro- 

 scopes, from the larjje binoculars (which some investigators 

 declare to be almost indispensable for certain researches) to the 

 smaller instruments sui'able for bacteriological and clinical 

 work, and the useful petrological micro.-copes. The microscope, 

 like the telescope of the present day, bristles with innumer- 

 able accessories, and Messrs. Beck's catalogue appears to contain 

 most of these adjuncts. A copy of the catalogue will be sent, 

 post free, on application. 



The Report of the Weather Bureau of the United States for 

 the year 1893, which has just reached this country, shows that a 

 general reorganisation has been effected, and that the work has 

 been carried on saccessfuUy. A very important publication of 

 the results of observations during 1891 and 1892, from upwards 

 of 2000 stations, has been recently issued. Every means is 

 taken to popularise the science ; the daily weather map is now 

 issued at seveniy-two stations of the Weather Bureau ojtside of 

 Washington, the na. nber distributed ana lally being over two 

 and a half millions. The circulation of the weekly weather 

 crop bulletins of the State services has also greatly in- 

 creased ; and continues to be the most valuable feature 

 of State weather service work. A large number of rail- 

 way companies co-operate with the Bureau in distributing 

 the daily weather forecasts by telegraph over their lines, and 

 whistle-signals are used to a considerable extent in some States. 

 The subject of seasonal forecasts is receiving the careful 

 attention of the Bareau, since the meteorological service of 

 India has indicated a path by which useful results can perhaps 

 be reached. The report also states that Prof. Bigelow continues 

 his studies of magnetism with sufficient prospect of success to 

 jastify the time and labaur expended. The library of the 

 Bureau now consists of nearly 20,003 books and pamphlets, 

 and the bibliography of meteorology comprises more than 

 65,000 titles. 



Cultivators anJ admireri of roses will be interested in 

 " Rhodologia "^a discourse on roses and the odour of rose — 

 by Mr. J. C. Sawer, published by W. J. Smith, North Street, 

 Brighton. Too much attention is generally given to the de- 

 velopment of colour, form, and size of the fljwer, little heed 

 being paid to the great variety of perfumes generated in the 

 beautiful petals. .Mr. Sawer says thit there are experienced 

 gardeners who can discriminate many varieties of roses in the 

 dark, recognising them by their perfumes. The pure odour of 

 rose is best represented by Rosa Damasccna, Miller, and R. 

 centifolia, Lin. The art of distilling roses appears to have 

 originated in Persia, and dates from about 1612. In 16S4 it is 

 certain that otto of rose was manufactured on a large scale at 

 Shiraz. Octo of rose was known in Europe, however, about 

 forty years sooner than in the East, where its manufacture was 

 first practised. We learn that at the present day the odorous 

 products of the rose are extracted in Bulgaria, France, Ger- 

 many, and to some extent in India, Persia, Tunis, .■\!geria, 

 Morocco, and Egypr. The rose cultivated in Bulgaria for the 

 otto is a variety of R. Damaictna — the red dam.ask rose. R. 

 centifolia, which in English gardens is grown as the cabbage 

 rose or Provence rose, is cultivated commercially in the south 

 of France. Mr. Sawer brings together in his pamphlet a m.iss 

 of details of interest to students, as well as to manufacturing 

 chemists and buyers of rose products. Rose growers (both 

 amateur and professional) should certainly read " Rhodologia." 



Two remarkable substances, carbazide or carbonyl nitride. 

 CONj, the nitrogen analogue of phosgene gas COCl^., and 

 di-urea, C0(XII. XIIjXO, the carbonyl derivative of di- 

 NO. 1306, VOt,. S l] 



hydrazine, are described by Prof. Curtius and Herr Ileidenreich 

 in the current Bcrichle. The former compound, which is con- 

 stitutionally formulated CO(N3).j, is found to be readily pro- 

 duced when the recently described hydrochloride of carbo- 

 hydrazide, CO{NII . NIIjHCl)^, is treated with a cold aqueous 

 solution of sodium nitrite. The reaction is a relatively simple 

 one, proceeding according to the equation : — 



CO(NH . NHjHCI), + 2NaN0o = C0(N3).j + 2NaCl -f 2HjO. 



Carbazide as thus produced is a colourless oil of most explosive 

 character. It explodes with great violence when merely 

 touched. When the oil is dissolved in ether, and the solution is 

 allowed to evaporate over calcium chloride, the pure substance 

 CONc i* '^f' '"^ 'o^g brittle crystals, which usually explode 

 spontaneously in a bright light, but may occasionally be pre- 

 served for some little time before disruption. The substance is 

 extremely volatile, and the vapour possesses a most penetrating 

 and stupefying odour, reminding one simultaneously of phosgene 

 gas and azoimide, N3H. Its composition is readily proved by 

 saponification with alkalies, which convert it into salts of azoi- 

 mide, which can be precipitated by silver nitrite. It also 

 reacts with aniline in alcoholic solution to produce carbanilide 

 and free azoimide. The second compound described in the 



.NH.NH. 

 communication, di-urea, CO /CO, is produced when 



~NH. NH/ 



NH . COOC2H5 

 the compound | , also recently described by 



NH . COOCoHj 



Prof. Curtius, is heated to 100° in a tube with hydrazine 

 hydrate. Di-urea crystallises readily from water in monoclinic 

 prisms melting at 270°. It behaves as a strong monobasic acid 

 «hich is capable of expelling carbonic acid fiom carbonates. 

 The ammonium salt, C-jH^N^O^ . NMj -f HoO ; barium salt, 

 (CoH3NjO.,)2Ba-r3H.jO; silver salt, C.HjNjO.Ag ; and diam- 

 monium (hydrazine) salt, CoHjN^O^, . N.jHj, have been prepared 

 and analysed. It is a very stable substance, quite dilTerent in 

 this respect from the explosive carbazide above described. 

 When heated, however, with concentrated hydrochloric acid in 

 a sealed tube to 1 50' it is decomposed into carbonic acid and 

 hydrazine. 



CO(NH . N1I)X0 -I- 2H3O = 2CO., -1- 2N„Hj. 



The hydrazine remains combined with the hydrochloric acid in 

 the form of a chloride, presumably diammonium chloride 

 NoH^CI. 



The additions to the Zoological Society's Gardens daring the 

 past week include a Brown Capuchin {Cebiis fiUiielltis) from 

 Guiana, presented by Mr. Graham S. Pownall ; two Common 

 Marmosets (Hapaie jacchus) Uom South-east Brazil, presented 

 by Mr. D. B. Macdougall ; two Black-backed Jackals {Cants 

 mesoinelai) from South .\frica, presented by Mr. Claude 

 Soulhey; three Crossbills [Loxia curvirostra), two Parrot 

 Crossbills {Loxia pilyopsittacus), an European White-winged 

 Crossbill {Loxia bifasciatus), a Yellow Bunting (Emberiza 

 aureola), two Northern Marsh Tits {Panis boreilis) from 

 Russia, presented by Captain A. Newnham ; a Double-ringed 

 Dove {Tiir/tirbiton/uahis] horn Java, presented by the Hon. 

 Rose Hubbard ; a Black Salamander (Sjlamandra atra), 

 European, presented by Mr. Maurice Suckling ; a Bonnet 

 Monkey {Macaciis sinicns) from India, two Lions {Felis 

 Uo, i 5 ) from Africa, deposited ; a Golden Plover {Charadritts 

 fluvialis), three Dunlins (Tringa alfina), European, 

 purchased ; a Spotted Pigeon (Coliimba maculosa), a Tri- 

 angular-spotted Pigeon (Culumba«uinea), two Vinaceous Turtle 

 Doves ( Turlur vinoieus), bred in the Gardens. 



