April 2S, 1889] 



NATURE 



613 



investigation of the fauna of Zanzibar, where he has been since 



last spring. A sum of £60 (Mk. 1200) has been sent to Dr. 

 Gustav "Weigand to help him in his linguistic and ethnographical 

 researches in the Balkan peninsula ; and Dr. Pomtow has 

 received £2^, (Mk. 500) towards the publication of his work on 

 Delphi. 



A CORRESPONDENT in Paris writes to us that the British Sec- 

 tion of the Paris Exhibition is nearly ready, and is much in 

 advance of most other parts of the Exhibition. 



The following are the dates of some of the Exhibition Con- 

 gresses which are to be held in Paris : — Technical Education, 

 July 8 to 12 ; Bibliography of the Exact Sciences, July 16 to 

 26; Chemistry, July 29 to August 3; Ballooning, July 31 to 

 August 3 ; Pigeons, July 31 to August 3 ; Hygiene, August 4 

 to II; Higher Education, August 5 to 10 j Physiological 

 Psychology, August 5 to 10 ; Geography, August 6 to 1 1 ; 

 Photography, August 10 to 17; Criminal Anthropology, 

 August ID to 17 ; Primary Education, August 11 to 19 ; Horti- 

 culture, August 16 to 21 ; Prehistoric Man and Remains, 

 August 19 to 26 ; Electricity, August 24 to 31 ; Chronometry, 

 September 2 to 9 ; Mines and Metallurgy, September 2 to 11 ; 

 Applied Mechanics, September 16 to 21 ; Meteorology, Sep- 

 tember 19 to 25 ; River Utilization, September 22 to 27 ; Com- 

 merce and Industry, September 22 to 28 ; and Hydrology and 

 Climatology, September 30 to October 15. 



Lectures will be delivered in Gresham College, on April 

 30, and May i, 2, and 3, by Dr. E. Symes Thompson, on the 

 medical aspects of life assurance. 



At a recent meeting, the Liverpool Geological Society ap- 

 pointed a Committee to report on the boulders occurring in the 

 glacial deposits of Liverpool and district. This Committee, after 

 full discussion, has reported that the investigations would be better 

 carried out if extended over the whole of Lancashire and Cheshire, 

 and by a larger Committee, consisting of representatives from all 

 parts of the two counties. The objects of the enlarged Committee 

 would be to examine and record the occurrence, nature, and facts 

 bearing on the mode of transport, of erratics in the glacial deposits 

 of Lancashire and Cheshire. If this suggestion meets with general 

 approval, a meeting of all interested in the question will be held 

 at some convenient centre at an early date. 



In a paper reprinted in Nature (vol. xxxiv. pp. 220, 239), 

 M. A. Blytt gave his views on variations of climate in the course 

 of time. Believing that periodical variations of climate are to 

 be attributed to changes in the strength of ocean-currents, he 

 finally traced back their origin to the precession of the equinoxes 

 and the eccentricity of the earth's orbit. He has now issued a 

 paper, with two supplementary notes, in which he seeks to 

 explain the displacement or alteration of beach lines, by changes 

 in the tidal-wave, caused by variations in the eccentricity of the 

 earth's orbit. Referring to his former conclusions, that dry 

 periods should be marked by chemical deposits, and rainy 

 periods by mechanically-formed sediment, he passes on to con- 

 sider the character of the Tertiary strata in the Paris and 

 Hampshire Basins. In the author's opinion, the alternation of 

 sediments of different nature indicates periodical variations in 

 climate ; and he endeavours to correlate these variations with 

 particular phases in the eccentricity of the earth's orbit, the 

 period or duration of which has been calculated in years. The 

 author also believes that the lengthening of the sidereal day has 

 had much influence on the form of the globe. This lengthening 

 has been caused mainly by the tidal wave, and as the centrifugal 

 force diminishes under such circumstances, strain accumulates in 

 the solid earth, until the limit of resistance is reached. Hence, 

 in the author's opinion, arose vertical displacements of beach - 

 lines. 



A REPORT from Sumatra states that the volcanic crater on the 

 west coast of the island, which has been quiet for several 

 centuries, was active during the middle of February. 



Severe shocks of earthquake, lasting for eight seconds, were 

 noticed at Zvomik in Bosnia, on April 2. The direction was 

 from south to east. 



We have received from the Deutsche Seewarte, the second 

 part of the Deutsche Ueberseeische Meteorologische Beobachtungen 

 (see Nature, vol. xxxvii. p. 444) containing complete observa- 

 tions made at six stations in Labrador during the year 1885, and 

 at one station in Walfisch Bay (south-west coast of Africa) dur- 

 ing the year 1887. Both sets of observations are carried on 

 under considerable difficulties ; in Labrador the rain-gauges are 

 frequently inaccessible on account of drifting snow-storms, and the 

 ordinary hygrometers are unmanageable during very low tempera- 

 tures. In Walfisch Bay the thermometers are often choked 

 by sand, or are liable to be affected by the intense radiation 

 from the ground. Nevertheless the work supplies very valuable 

 materials from remote regions where little is yet known about 

 the peculiarities of the climate. 



A carbohydrate of the empirical composition CgHjoOs, 

 and possessing properties very closely resembling those of the 

 arabin of " gum arable," has been artificially prepared by Prof. 

 Ballo, of Buda-Pesth. This achievement is the outcome of an 

 attempt to reproduce the conditions under which the acids of the 

 vegetable world are reduced by chlorophyll. It was assumed 

 that the iron of chlorophyll is present in the ferrous state, and 

 tartaric was the acid upon which operations were commenced. 

 About equal quantities of tartaric acid and ferrous sulphate were 

 dissolved in a minimum bulk of water, and the solution was 

 warmed upon a water-bath. In a short time a greyish-yellow 

 precipitate began to separate. The whole was then evaporated 

 until it completely solidified on cooling. The cold mass was 

 next extracted with alcohol and the extract again evaporated. 

 The residue thus left by volatilization of the alcohol was neutra- 

 lized with milk of lime, and the filtered solution again placed on 

 the water-bath. It was now noticed that as the water was 

 gradually expelled the contents of the evaporating dish became 

 more and more viscid, until, finally, a sticky mass was left, 

 reminding one most forcibly of gum arable. Knowing that 

 this familiar article of commerce chiefly consisted of the calcium 

 and potassium compounds of arabin, the likeness was felt to be 

 somewhat indicative of the formation of an arabin-like substance. 

 On allowing the concentrated syrup to cool, a calcium salt 

 readily crystallized out, yielding on analysis numbers point- 

 ing to the formula (C6H905)2Ca 4- 9H2O. From this the 

 free carbohydrate was obtained in two ways, either 

 by precipitation of the solution . in water with lead acetate 

 and subsequent decomposition of the lead salt with sulphuretted 

 hydrogen, or by addition of the calculated quantity of oxalic 

 acid. The syrup of " iso-arabin," as it is provisionally termed, 

 was further purified by repeated treatment with alcohol and 

 ether and subsequent re-evaporation. It was then allowed to 

 stand over sulphuric acid, some specimens for a month and 

 others so long as a whole year. Each of these specimens, on 

 combustion, yielded numbers indicating the empirical formula 

 CflHjoOs. Iso-arabin is an almost colourless syrup, readily 

 mixing with water. It does not reduce Fehling's solution, but 

 rotates the plane of polarization to the right. It behaves, in 

 short, exactly like the carbohydrates of the (C6Hio05)« group. 

 The potassium salt, obtained by decomposing the calcium salt 

 with potassium carbonate, also crystallizes well in large an- 

 hydrous crystals. In addition to iso-arabin itself, a small 

 quantity of its hydrate, CftHjoOj -I- HjO, is also formed by the 

 action of ferrous sulphate upon tartaric acid, and separates Jout 

 in crystals from the alcoholic washings of the crude iso-arabin. 



