428 



NATURE 



[March 6, 1890 



A SHORT note on diethylene diamine, C2H4^ ;C2H4, is 



■contributed to the new number of the Berichte of the German 

 Chemical Society by Dr. J. Sieber, of Breslau. It was obtained 

 by the action of ethylene dibromide, CoH4Br,, upon ethylene 



diamine, C«Ha , a liquid boiling at 123° C. Upon treat- 



\NH2 

 ing the product of this reaction with caustic potash, an oily 

 liquid separated, consisting of a mixture of bases. The separ- 

 ated liquid was next dehydrated as completely as possible, and 

 then submitted to fractional distillation, when the portion boiling 

 between l68"'-l75° was found to consist of diethylene diamine 

 admixed with a little water. The affinity of the base for water is, 

 in fact, so great that it was found impossible to remove the last 

 traces of moisture. Diethylene diamine, however, readily forms 

 salts which can be isolated in a state of purity, and the analyses 

 of which prove the composition of the base itself. The hydro- 

 NH.HCl 



chloride, CoH4<^ pCjHj , crystallizes in beautiful white needles, 



NH.HCl 

 very soluble in water, but insoluble in alcohol. The platino- 

 chloride, C4HjoN2(HCl)oPtCl4, forms fine yellow needle-shaped 

 crystals, readily soluble in hot water, but difficultly soluble in 

 boiling alcohol. A very beautiful salt is also formed with mercuric 

 chloride, C4HijNo(HCl)2HgCl2, consisting of star-like aggregates 

 of acicular crystals, also soluble in hot water, but reprecipitated 

 by the addition of alcohol. 



Drs. Will and Pinnow communicate to the same journal 

 their report upon the analysis of the remarkable meteorite of 

 Carcote, Western Cordilleras, Chili. The great mass of this 

 meteorite, 80 per cent., is found to consist of two silicates. 

 One of them is readily decomposed by hydrochloric acid, and 

 possesses the composition and optical characters of olivine, 

 (MgFe)2Si04. The other is unattacked by hydrochloric acid, 

 and exhibits the chemical and crystallographical characters of a 

 member of the diopside group. Interspersed among the silicates 

 are smaller quantities of chrome ironstone, bronze-like sulphide 

 of iron, probably troilite, and light steel-grey nickeliferous iron. 

 The latter is not only found in minute particles, but also fre- 

 quently in small plates which show the Widmannstadt figures in 

 the form of an extremely fine rectangular network. Here and 

 there are found silver- white crystals of rhabdite, one of the forms 

 of nickeliferous iron. By far, however, the most interesting 

 substance contained in the meteorite, is a form of crystalline 

 elementary carbon, dull black in appearance and of extreme 

 hardness, at least 9. It is, in fact, a variety of black diamond, 

 and its presence in the meteorite affords considerable ground for 

 speculation. Carbon is further present in the form of organic 

 substances soluble in ether, and these substances carbonize upon 

 heating, evolving the usual odour of burning organic matter. 

 Hence this meteorite is an extremely interesting one, and forms 

 another addition to the fast-accumulating list of those in which 

 carbon forms a not insignificant ingredient. 



OUR ASTRONOMICAL COLUMN. 

 Objects for the Spectroscope. 

 Sidereal Time at Greenwich at 10 p.m. on March 6 = 

 5h. 58m. 19s. 



(i) G.C. 1713 ... 



(2) 120 Schj. 



(3) a Hydrae 



(4) a Cancri 



(5) 124 Schj. 



it) T Monocerotis 



Mag. 1 



Colour. 



R.A. I ago. Decl. 1890 



6-5 

 3 



5 "4 

 Var. 



Reddish-yellow. 



Yellow. 

 Yellowish-white. 

 Reddish-yellow. 



Yellow. 



Remarks. 

 (r) This bright oval nebula is now in a very convenient posi- 

 tion for observation. I am not aware that the spectrum has 

 been recorded. It is about 8' long, and 3' broad, and is thus 

 described in the General Catalogue : ' ' Very bright, very large, 

 very much elongated 40° "9, gradually much brighter in the 

 middle." The description is very suggestive of the Great 

 Nebula in Andromeda, and if, as in that case, the spectrum at 

 first appears continuous, closer scrutiny may reveal irregularities. 

 The brighter parts, assuming that they exist, should be compared 

 with the spectrum of carbon. 



(2) According to the observations of D'Arrest, Secchi, and 

 Vogel, this is a fine example of the stars of Group II. Duner 

 states that all the bands i to 10 inclusive are excessively wide 

 and dark, and that the spectrum is totally discontinuous. The 

 star, therefore, affords a good opportunity for further observa- 

 tions of the bright carbon flutings with the object of establishing 

 the cometary character of the stars .of this group. It may be 

 remarked that the citron band of carbon need not enter into this 

 comparison, as it will be masked by the dark fluting of 

 manganese (band 4). 



(3) A star of the solar type (Konkoly). The usual differential 

 observations are required. 



(4) A star of Group IV. (Vogel). The usual observations are 

 required. 



(5) This star has a "very fine" spectrum of the Group VI. 

 type, notwithstanding its low altitude in our latitude (Duner). 

 The principal bands, 6, 9, and 10, are very dark, and the 

 secondary bands, 4 and 5, are also well seen. Further observa- 

 tions, with special reference to line or other absorptions, are 

 suggested. 



(6) A maximum of this short-period variable will occur on March 

 8. Gore gives the period as 26'76 days, and the magnitudes at 

 maximum and minimum as 6 '2 and 7 "6 respectively. There is 

 still a little doubt with regard to its spectrum. In his spectroscopic 

 catalogue, Vogel writes it Il.a? Ill.a, giving the magnitude at 

 the time of observation as 7'3. In all probability the spectrum 

 is intermediate between Group II. and Group III., perhaps 

 something like Aldebaran, A. Fowler. 



The Total Solar Eclipse of December 22, 1889. — 

 M. A. De La Baume Pluvinel, who was located in Royal Island, 

 about 30 miles north of Cayenne, during this eclipse, communi- 

 cated his results to the Paris Academy on the 17th ult. 

 (Comptes retidus. No. 7, 1890). An examination of the pheto- 

 graphs of the corona which were obtained leads to the 

 conclusions that — 



(1) The corona presented the same general aspect as on 

 January I, 1889. 



(2) The extension of the corona was small, being about 18' at 

 the solar equator, and about 6' at the poles, and in this respect 

 resembled the coronae of 1867 and 1878, thus confirming the 

 intimate relation that exists between the intensity of extra-solar 

 phenomena and the frequency of sun-spots. 



(3) The aspect of the luminous aigrettes which constitute the 

 corona, and notably the curved form of the aigrettes in the 

 neighbourhood of the poles, seem to prove the existence of 

 streams of matter submitted to two forces — a force of projection 

 normal to the solar sphere, and a centrifugal force developed by « 

 the sun's rotation. 1 



Comets and Asteroids discovered in 1889. — * 



Comet a 1889. — Discovered on January 15, a little before 

 dawn, by Mr. W. Brooks at Geneva, N.Y., U.S.A. The comet 

 was moving rapidly from east to west, and was not afterwards 

 observed. 



Comet b 1889. — Discovered by Mr. Barnard, of the Lick 

 Observatory, on March 31 ; it was then very feeble and difficult 

 to see. After perihelion passage, the comet was observed at 

 Ann Arbor on July 22, near the position assigned to it by M. 

 E. Millosevich. 



Comet c 1889. — Also discovered by Mr. Barnard, on June 

 23, as a faint nebulosity without condensation or tail. Not 

 observed after August 6. Dr. Berberich determined the ele- 

 ments of this comet on the hypothesis of an elliptic orbit, and 

 found that its period was 128 years. 



Comet d 1889. — This comet, the most interesting of those 

 observed last year, was discovered by Mr. Brooks, of Geneva, 

 U.S., on July 6. It is periodic, the time of revolution being 

 7 '04 years. On August i, Mr. Barnard found that the principal 

 comet was accompanied by four companions. Mr. Chandler 



