February 4, 1892] 



NATURE 



325 



Castella is of opinion that the amount of wine produced in the 

 colony will soon be very considerable. He recommends that 

 the vine-growers of each district should agree among themselves 

 to produce only one definite type of wine, and that it should be 

 known by the name of the district — such as Rutherglen, Great 

 Western, Bendigo, Mooroopna, and so forth. The label on a 

 bottle would thus give some idea of the contents. To name 

 wine from the sort of grape is useless. Two Rieslings — for 

 instance, one grown on the Yarra and the other on the Murray 

 — differ as much as hock and sherry. 



Wr. Clement Reid read an interesting paper the other 

 evening before the Norfolk and Norwich Naturalists' Society 

 on the natural history of isolated ponds. He selected as 

 typical examples the isolated ponds dug on the South Downs to 

 store water for cattle. These ponds are from 300 to 400 feet above 

 sea-level, supplied by rain and condensation, and quite uncon- 

 nected with any stream, often far from a road or path ; and it 

 appears most unlikely that seeds of the plants, or eggs of the 

 animals, which he found in considerable numbers and variety, 

 can have been conveyed thither by human agency. Both the 

 eggs and the seeds must, he thinks, have been transported 

 chiefly on the feet of birds. 



Messrs, Longmans have in the press and will shortly 

 publish a new and revised edition of Sir Philip Magnus's 

 " Lessons in Elementary Mechanics." The book, which has 

 already passed through seventeen editions, has been entirely re- 

 written by the author. It contains several new sections, and especial 

 attention has been given to the subject of units and to the 

 explanations of terms. No change, however, has been made in 

 the general arrangements of the book. A key containing full 

 solutions of all the exercises and examination questions, many of 

 which are new, is ready for press, and will be published about the 

 same time as the new edition. 



A BOOK by Prof. A. Targioni Tozzetti on the insects and 

 other animals which injure tobacco has recently been published. 

 Of his 300 pages of text, 270 are devoted to insects, 6 to verte- 

 brates, 7 to snails, 10 to arachnids, and I to earthworms. 

 Dealing with the cigarette beetle {Lasiodenna serricorne), which, 

 of all tobacco insects, does most damage in America, Prof. 

 Tozzetti recommends as a remedy a thorough use of chloroform, 

 bisulphide of carbon, and hydrocyanic acid gas in disinfecting 

 warehouses and manufactories ; and he advises, where possible, 

 the submersion of the tobacco in 90 parts of water for forty- 

 eight hours. Insect Life says of this advice that it is " evidently 

 not based on experience, and not appreciative of the ease with 

 which tobacco is spoiled for the trade." 



In the last sentence of Mr. Frederick J. Smith's letter on 

 " A Simple Heat Engine" (Nature, p. 294), for "fall" read 

 "pull." 



A SERIES of remarkable compounds of the halogen salts of 

 the rare metal caesium with two more atoms of chlorine, bromine, 

 or iodine, are described by Messrs. Wells and Penfield in the 

 January number of the American Journal of Science. The fact 

 was accidentally discovered that when bromine is added to a 

 concentrated solution of caesium chloride, CsCl, a dense bright- 

 yellow precipitate is produced. When the contents of the test- 

 tube are warmed, this precipitate dissolves, but on cooling the 

 same substance separates out in the form of large orange- 

 coloured crystals. Upon analysis these crystals are found to 

 possess the composition CsClBr^ This remarkable observation 

 has led to the preparation of a series of eight such salts, each 

 containing one atom of czesium and three halogen atoms. The 

 formulse of these compounds are Cslj, CsBrL, CsBroI, CsClBrI, 

 CsCloI, CsBrj, CsCIBr.,, and CsCUBr. They all crystallize 

 well, generally in large brilliant prisms. Those of CsL, are 

 NO. I 162, VOL. 45] 



black and almost opaque ; those of CsBrL, dark reddish-brown 

 by reflected and deep red by transmitted light ; CsBroI forms 

 crystals of a bright cherry-red colour ; while the crystals of 

 CsClBrI, CsBrj, and CsClBrj are tinted with various shades 

 of orange. The compound CsCljBr forms bright yellow 

 crystals, the lightest coloured in the whole series. Two other 

 possible salts of the series, CsClL and CsClj have not yet been 

 obtained. The general method by which the above eight salts 

 were prepared consisted in dissolving the haloid salt of csesium 

 employed in water, adding the requisite quantity of iodine or 

 bromine, or leading a stream of chlorine through the solution, 

 and cooling or evaporating to the crystallizing point. The salts 

 are remarkably stable, they may all be preserved for any length 

 of time in corked tubes or bottles. They form an isomorphous 

 group, all crystallizing in the rhombic system. An important 

 relation has been discovered between the crystallographical 

 constants of the first five members of the series, those con- 

 taining iodine. The ratio of two of the axes remains almost 

 constant throughout the whole of the five, while the third varies 

 with the molecular weight. 



The formation of salts of the nature above described, in 

 which a compound such as caesium chloride, which is usually 

 considered as fully saturated, actually combines directly with 

 two more atoms of a monad halogen element, is a most im- 

 portant and interesting fact considered in connection with the 

 general subject of residual affinity. Caesium, as is well known, 

 is the most electro-positive element yet discovered, and that it 

 should exhibit this phenomenon of residual affinity in so startling 

 a manner is perhaps not surprising. Moreover, Johnson in the 

 year 1877 obtained a tri-iodide of potassium, KI3, and also in 

 1878 an analogous ammonium compound, NH4T3. The question 

 of the constitution of such salts is a most complex one, but the 

 balance of evidence, particularly that afforded by the crystallo- 

 graphical measurements, is decidedly in favour of considering 

 them as double salts, and not as salts of trivalent caesium. The 

 acceptance of a possible trivalency of caesium would of course 

 be in direct antagonism to the teaching of the periodic generaliza- 

 tion, and Prof. Mendeleeff^ himself considers the two extra 

 atoms of iodine in potassium tri-iodide to be united much in 

 the same manner as the water taken up by many salts upon 

 crystallization. 



The additions to the Zoological Society's Gardens during the 

 past week include a Grey Ichneumon {fferfesles griseus 6 ) from 

 India, presented by Mr. R. Meinertzhagen ; a Lesser White- 

 nosed Monkey (Cercopiihectis pelaurista ?) from West Africa, 

 deposited ; two Snow Buntings {Plectrophanes nivalis), a Yellow 

 Bunting (Emberiza citrinella), two Reed Buntings (Emberiza 

 schanicliis), British, purchased ; seven Coypus {Myopotaiiius 

 coyptts), born in the Gardens. 



OUR ASTRONOMICAL COLUMN. 



New Star in the Milky Way.— The following circular 

 was issued from the Royal Observatory, Edinburgh, 1892, 

 February 2 : — 



Yesterday an anonymous post-card was received here bearing 

 the following communication : — 



" Nova in Auriga. In Milky Way, about two degrees south 

 of X Aurigse, preceding 26 Aurigae. Fifth magnitude, slightly 

 brighter than x-" 



At 6h. 8m. G.M.T. the star was easily found with an opera- 

 glass. It was of a yellow tint, and of the sixth magnitude, 

 being equal lo 26 Aurigse. Examined with a prism between 

 the eye and the eye-piece of the 24-inch reflector, it was im- 

 mediately seen to possess a spectrum very like that of the Nova 

 of 1866. The C-line was intensely bright, a yellow line about 

 D fairly visible ; four bright lines or bands were conspicuous in 

 the green ; and, lastly, a bright line in the violet (probably H7) 

 was easily seen. 



A telegraphic notice was sent to Greenwich in the afternoon. 



