.182 



NATURE 



\June 21, 1S83 



6500 atm ispheres he finds that sulphur combines with mag- 

 nesium, zinc, iron, cadmium, bismuth, lead, copper, silver, tin, 

 and a'ltimony. Sulphur and phosphorus do not combine when 

 compressed together [Berichte, xvi. 999). 



Benzene is perhaps the most important body in the whole 

 range of chemistry, not on account of any intrinsic interest in 

 the substance it-elf, but because of the immense number of its 

 derivatives. The constitution of the^-e derivatives mu-4 depend 

 upon the structure of the benzene molecule itself, and this pro- 

 blem is therefore one of the most interesting that presents itself 

 to the chemist. Any idea that can throw light upon this subject 

 is w irthy of attention, and the more so as long as the least doubt 

 exists as to whether benzene can yield more than three di, tri, or 

 tetra derivatives, or more than one mono or penta derivative, 

 the substituting groups being the same. Again, it is possible 

 that benzene may exist in two or more isomeric modifications 

 (disregarding dipropargyl), and the difference found by V. Meyer 

 (Ber. xv. 2893) between two sarnies of benzene, both pre- 

 samably pure, would see n to point in this direction. The mere 

 fact, therefore, that one formula is good and useful is no con- 

 demnation of any other formula that may be proposed. M. 

 MendeleefT has suggested that benzene may be regarded as a 

 normal butane, in which six hydrogen atoms are replaced by 

 two triad groups, CH. If we allow that benzene is best repre- 

 sented as containing six CH groups, and there seems as yet no 

 reason for departing fron this supposition, then this replace- 

 ment may take place in two ways, as shown by the following 

 formula; : — 



CH3 — CH 2 — C Hj, — CH 3 



Normal butane. 



CH 



CH— CH— CH— CH 

 CH CH 



CH 



CH 



CH 



Benzenes derived therefrom. 



These two benzene formulae may be conveniently written thus :- 



Y 



Yl 



and these expressions show at a glance the difference between 

 them. The second is identical with Ladenburg's prism formula, 

 the advan' ages of which do not need recounting. The first, so 

 far a> dou >le and single Unkings are concerned, is intermediate 

 between the prism formula and Kekule's. It lends itself in a 

 particularly ready way to the expression of more complex 

 Formulae, as of naphthaline, &c. , but does not show the hexad 

 nature of the benzene molecule. Moreover, it shows possible 

 two mono or penta derivatives, and five each di, tri, and tetra 

 derivative-, a capability that is not yet needed ; and a formula 

 should be a concise expression of facts an d -hnuld as far as 

 possible show the limits of tho^e facts. Thus, however valuable 

 the suggestion of M. MendeleefT may be as showing a possible 

 method of synthesising benzene, it does not appear to be prac- 

 tically useful as indicating its constitution, though the future 

 chemistry of benzene may require such a formula as the one 

 referred to above. 



Prof. MENDELEEFF, to avoid the superheating which takes 

 place during ordinary fractional distillation with a dephlegmator 

 tube, has devised a modified method for the oils from Baku 

 petroleums boiling between 15° and 150°, which consists in 

 passing the vapours from the distilling llask by means of the 

 dephlegmator, or delivery tube, to the b ittooiof a second similar 

 flask, and from this to a third, and so on ; the heated vapours 

 rom the one providing the nece^siry heat for the distilUtion of 

 1'ie next, &c. In this manner a great number of fractions at 

 i itervaL of two degrees were obtained. By comparing b iling 

 p lints and specific gravities of products the author concludes that 

 Baku oils contain similar hydrocarbons to American petroleum, 

 and in addition a hydrocarbon boiling at 55° and same specific 

 gravity as hexan with the properties of an unsaturated compound. 

 The great bulk of the Caspian petroleums appears to consist, in 

 addition to derivatives of marsh gas, of ^,11^,, hydrocarbons, 

 and also some members of the C„H n or acetylene series. 



.Some interesting results have been obtained by Spring (Ber. 

 Ber.) by washing precipitated sulphide of copper for several 

 weeks until all traces of salts were removed. It was then found 



that the sulphide dissolved to a black liquid, with slight green 

 fluorescence, in water. The solution might be boiled ind 

 evaporated without change ; slight trices of salts caused preci- 

 pitation. The author has also obtained sulphide of tin and 

 oxides of antimony and manganese in a condition perfectly 

 soluble in water. Sulphide of tin on evaporation of its solution 

 in vacuo forms a transparent red glass. 



GEOGRAPHICAL NOTES 



On June 6 Baron Norde.skjbld's Greenland expedition arrived 

 at Reykjavik in the steamer Sophia. The Sophia lay at Reyk- 

 javik for a few days, and in the meantime Baron Nordenskjbld 

 and the geologists of the pirty examined the coal deposits which 

 occur in Be guti ord. Dr. Arpi, a Swedish philologist, who has 

 resided some time in Iceland and acquired a thorough knowledge 

 of the language, accompanied the expedition thither, and will, 

 along with two other men of science, remain in Iceland after the 

 Sophia has left. 



We learn from Science that a party for the relief of the ob- 

 servers under Lieut. Greely at Lady Franklin Bay was to leave 

 St. John's, Newfoundland, on one of the steam sealiug-vessels 

 belonging to that port, about June 15, probably accompanied by 

 a naval vessel as tender. It will he commanded by Lieut. E. 

 A. Garlington, U.S.A., and composed of twelve men, of whom 

 ten are stated to be old sailors and accustomed to the u-e of 

 boats. Twenty dogs, native drivers, and a supply of fur 

 clothing, have been secured at Godhavn, Greenland. The party 

 at Lady Franklin Bay will be reached and withdrawn if the state 

 of the ice permits. If not, the relief party is to belauded on 

 Littleton Island, and while part of them are engaged in preparing 

 winter quarters, Lieut. Garlington will endeavour 'o open com- 

 munication by sledges with Greely's people. In the failure of 

 the fir-t attempt, another w ill be made in the spring of 1884. It 

 is to be hoped, if Greely is not reached, that an attempt will be 

 nude to leave at Cape llawkes or Cape Sabine, if not the relief 

 party as a whole, which would be best, at lea t a boat by which 

 the open water to be anticipated between those points and Little- 

 ton Island next year (1SS4) may be pa el ly a repealing party, 

 which might well find their own boat un ea worthy after dragging 

 it over many miles of hummocky ice, if, indeed, they did not 

 find themselves obliged t" abandon it. Further, the schooner 

 Leo is on the point of sailing for Point Barrow to withdraw the 

 signal- service observing party under Lieut. Kay, in compliance 

 with the act passed by the last Congress. To utilise the oppor- 

 tunity. Mr. Marr, of the U.S. Coast-Survey, will accompany the 

 vessel with the design of making absolute magnetic determina- 

 tions, of fixing the astronomical position of the station, and of 

 making pendulum observations. 



In a communication from the Russian Geographical Society 

 we are informed that Col. Prejevalsky is ab m to start on hi> 

 fourth journey to Central Asia, accompanied by two officers and 

 seventeen men. The Emperor has granted to the Society 43,000 

 roubles for the purpose of Col. Prejevalsky's j mrney. The 

 Society is also sending out a new expedition under M. Potanin, 

 who i- now completing the publication of the two last volumes 

 on his journey of 1S79-80. lie will start 111 July for South-East 

 Mongolia and the adjacent parts of China; he will be accom- 

 panied by a naturalist and M. Skassi, the companion of Severtzov 

 in hi, exploration of the Pamir. The funds are being supplied 

 partly by the Society and partly by M. Sookachef, a Siberian 

 merchant. 



In the same communicati in we are informed that the average 

 temperature of January and February at the Ru-sian Polar station 

 at Sagastyr, on the mouth of the Lena, was about - 50 C. 

 Thanks to the Governor-General of Eastern Siberia there has 

 been organised a special postal service between Jakut>k and 

 Sagastyr once a month. The observing party will most probably 

 remain at the station up to the end of October, i.e. until the 

 river is frozen. 



The la,t number of the Zeitsckri/t d,-r Gesellschafl fur 

 Erdknnde zit Berlin (Bd, lS, Heft 2) contains a paper by Hen- 

 van Langegg, entiled " Nara eine alte Kaiserstadt," describing 

 the town of Nara, not far from Kioto, in J ipan, at one time the 

 capital of the country, and still much renowned for it-, temples 

 The celebrated colossal statue of Bu ldha there is fully de-cribed. 

 The following figures give some notion of its dimensiois: — Its 

 weight is 500,000 kilog. ; 3,000,000 kilog. of wood were con- 



