November 12, 1891] 



NATURE 



4» 



by Warren Upham ; the mineral resources of the province of 

 Quebec, by R. W. Ells ; the surface geology of Southern New 

 Brunswick, by R. Chambers ; chemical contributions to the 

 geology of Canada from the laboratory of the Survey, by G. C. 

 Hoffmann ; mining and mineral statistics of Canada, by H. P. 

 Brumell ; division of mineral statistics and mines, by E. D. 

 Ingall and H. P. Brumell ; annota'ted list of the minerals 

 occurring in Canada, by G. C. Hoffmann. 



The administration of forests seems to be, on the whole, one 

 of the most satisfactory departments of public activity in India. 

 Dr. Ribbentrop, in his report for the year 1889-90, states that 

 over 4200 square miles were added to the area of forest estates 

 under control, thus bringing the total area up to nearly 105,500 

 square miles. The gross revenue exceeded 153 lakhs of rupees, 

 giving a surplus over expenditure of nearly 73 lakhs, or an 

 increase in a single year of 15 lakhs. The surplus in 1885 was 

 only 41 lakhs. It is believed that this rate of increase may be 

 maintained, as the rich forests of Upper Burma have still to be 

 opened out. 



In a recent communication from Alta Verapaz, a department 

 in Guatemala {Met. ZeiL), Dr. Sapper describes the climate. 

 The position is on the north slope of a hill-range stretching east 

 and west, and the large rainfall (it has a rainy season in winter, 

 as well as that in tummer common to the whole of Central 

 America) apparently affects the frequency of earthquakes. For 

 the district is of limestone and dolomite, and honeycombed 

 with caverns and subterranean watercourses, and heavy rains 

 lead to a collapse of such cavities, so that towards the end of 

 the summer rain season, and still more towards that of winter, 

 the number of earthquakes and tremors is distinctly increased. 

 The winter of 1889-90 had unusually heavy rains, and the 

 earthquakes were also unusually numerous (seventeen in 1890 

 as against five the previous year). 



A PAPER upon the sulphides of boron is communicated by M. 

 Paul Sabatier to the September number of the Bulletin de la 

 Societe Chimiqiie. Hitherto only one compound of boron with 

 sulphur has been -known to us, the trisulphide, B2S3, and con- 

 cerning even that our information has been of the most incom- 

 plete description. Berzelius obtained this substance in an 

 impure form by heating boron in sulphur vapour, but the first 

 practical mode of its preparation in a state of tolerable purity 

 was that employed by Wdhler and Deville. These chemists 

 prepared it by allowing dry sulphuretted hydrogen gas to stream 

 over amorphous boron heated to redness. Subsequently a 

 method of obtaining boron sulphide was proposed by Fremy, 

 according to which a mixture of boron trioxide, soot, and oil are 

 heated in a stream of the vapour of carbon bisulphide. M, 

 Sabatier finds that the best results are obtained by employing 

 the method of Wcihler and Deville. The reaction between 

 boron and sulphuretted hydrogen only commences at red heat, 

 near the temperature of the softening of glass. When, how- 

 ever, the tube containing the boron becomes raised to the 

 temperature, boron sulphide condenses in the portion of the 

 lube adjacent to the heated portion ; at first it is deposited in a 

 state of fusion, and the globules on cooling present an opaline 

 aspect. Further along the tube it is slowly deposited in a 

 porcelain-like form, while further still the sublimate of sulphide 

 takes the form of brilliant acicular crystals. The crystals consis 

 of pure B2S3 ; the vitreous modification, however, is usually 

 contaminated with a little free sulphur. Very fine crystals of 

 the trisulphide may be obtained by heating a quantity of the 

 porcelain-like form to 300° at the bottom of a closed tube whose 

 upper portion is cooled by water. The crystals are violently 

 decomposed by water, yielding a clear solution of boric acid, 

 sulphuretted hydrogen being evolved. On examining the porce- 

 lain boat in which the boron had been placed, a non volatile 

 NO. II 50, VOL. 45] 



black substance is found, which appears to consist of a lower 

 sulphide of the composition B4S. The same substance is ob- 

 tained when the trisulphide is heated in a current of hydrogen ; 

 a portion volatilizes, and is deposited again further along the 

 tube, while the residue fuses, and becomes reduced to the unal- 

 terable subsulphide B4S, sulphuretted hydrogen passing away in 

 the stream of gas. 



Two selenides of boron, B.^Ses ^^^ B^Se, corresponding to 

 the above-described sulphides, have also been prepared by M . 

 Sabatier, by heating amorphous boron in a stream of hydrogen 

 selenide, H^Se. The triselenide is less volatile than the tri- 

 sulphide, and is pale green in colour. It is energetically de- 

 composed by water, with formation of boric acid and liberation 

 of hydrogen selenide. The liquid rapidly deposits free selenium, 

 owing to the oxidation of the hydrogen selenide retained in 

 solution. Light appears to decompose the triselenide into free 

 selenium and the subselenide B4Se. 



Silicon selenide, SiScj, has likewise been obtained by M. 

 Sabatier by heating crystalline silicon to redness in a current of 

 hydrogen selenide. It presents the appearance of a fused hard 

 metallic mass incapable of volatilization. Water reacts mos^ 

 vigorously with it, producing silicic acid, and liberating hydrogen 

 selenide. Potash decomposes it with formation of a clear 

 solution, the silica being liberated in a form in which it is readily 

 dissolved by alkalies. Silicon selenide emits a very irritating 

 odour, due to the hydrogen selenide which is formed by its re- 

 action with the moisture of the atmosphere. When heated to 

 redness in the air it becomes converted into silicon dioxide and 

 free selenium. 



The additions to the Zoological Society's Gardens during the 

 past week include a Macaque Monkey {Macacits cynomolgus i ) 

 from India, presented by Mr. G. E. Lidiard ; two Senegal 

 'Yo\ixz.Q.o\x%{Corythaix persa),^ Madagascar Porphyrio {Porphyrio 

 madagascaricnsis) from West Africa, presented by Mr. J. B. 

 Elliott ; a Blue-fronted Amazon (Chrysotis irsiiva) from Brazil, 

 presented by Mrs. H. R. Warmington ; two Puff Adders 

 (Vipera arietans) from South Africa, presented by Messrs. 

 Herbert and Claude Beddington ; two Tree Boas {Corallus 

 hortnlanus) from St. Vincent, W.I., presented by H.E. the 

 Hon. Sir Walter F. Hely Hutchinson, K.C.M.G. ; a Tree Boa 

 [Corallus hortnlanus) from Demerara, presented by Mr. J. J. 

 Quelch, C.M.Z.S. ; a Black-headed Lemur {Lemur brtmtieus) 

 from Madagascar, a Brown Capuchin (Cedus fattiellus) from 

 South America, a Black-headed Caique {Caica iitelanocephala) 

 from Demerara, a Red and Blue Macaw (Ara macao) from 

 Central America, deposited ; a Black-headed Caique {Caica 

 nielanocephala) from Demerara, purchased. 



OUR ASTRONOMICAL COLUMN. 



Outburst ok Dark Spots on Jupiter.— Attention has 

 been called by several observers to a number ofdark spots which 

 have appeared lately on the first belt north of the north equa- 

 torial belt of Jupiter, in about latitude lo". Mr. Denning 

 derived a period of rotation of 9h. 49m. 27 •2S. from his observa- 

 tions of one of these objects between August 2i and September 

 15 {Obsei-va'ory, October 1891). A change then occurred, f )r 

 this spot, and others near it, were found to have a rotation period 

 of 9h. 49m. 442s. from September 15 to October 15, This- 

 sudden change of 17 seconds in the rate of motion of a region of 

 some extent is most remarkable. A series of photographs of 

 Jupiter were taken at Lick Observatory in August, which, 

 according to Mr. Stanley William?, "are of such a degree of 

 excellence that an examination of them is almost like looking at 

 the planet itself" {Obswatory, November 1891). These photo- 

 graphs show six or seven dark spots, and a comparison of them 

 with a sketch made about one rotation later clearly indicates a 

 displacement of the spos with reference to the great red spot» 



