552 



NATURE 



[April s. 1888 



Berlin. 



Meteorological Society, March 6. — Dr. Vettin, President, 

 in the chair. — Dr. Zenker gave an account of his work, which 

 has been awarded a prize by the Paris Academy, on the distri- 

 bution of heat over the surface of the earth. When considering 

 the total heat which reaches the earth's surface, it is of course 

 dependent upon the distance of the sun, and is greater at perihelion 

 than at aphelion in the ratio of the inverse square of the sun's 

 distance. The varying ellipticity in outline of the earth in its 

 various positions has no influence on the heat received owing to 

 the extremely slight difference thus produced. If any one point of 

 the earth's surface is alone considered, then the heat received is 

 determined by the sine of the sun's altitude or the cosine of its 

 zenith distance, for which the speaker gave an equation ex- 

 pressed in terms of amplitude and declination. From the above 

 relationships it follows, leaving the air out of account, as has 

 usually been the case, that the heat received by the Pole on a 

 summer day is greater than that whijh falls on a point at the 

 equator. Thus taking as unit the heat received during twenty- 

 four hours by a place at which the sun is in the zenith, the North 

 Pole receives an amount of heat represented by 0*397, and a point 

 on the equator an amount represented by 0*292. But the air 

 absorbs a large part of the sun's heat. The speaker considered 

 it unreliable to estimate the height of the atmosphere from the 

 amount of heat-absorption, as is frequently done, inasmuch as 

 the chief absorption takes place in the deeper layers of the air. 

 For the determination of the coefficient of absorption Dr. Zenker 

 accepts the values obtained by Langley from his bolometric ex- 

 periments, with a reservation, however, as regards the absorption 

 which takes place in its highest layers, which he did not admit. 

 One factor of great importance is the diffusion of heat, already 

 described by Clausius, from the small particles of water, dust, and 

 air in the atmosphere, which are calculated under other definite 

 assumptions. Another factor which must not be lost sight of is 

 the reflection of heat at the earth's surface ; this is calculated for 

 the three cases of a surface of water, land, and snow. Special 

 tables are given of the heat reflected from these three kinds of 

 earth-surface for separate places per day and per year. The ap- 

 plication of this theoretical part of the research to the climatology 

 of the earth's surface, the speaker intends to lay before the Society 

 at some future time. — Dr. Less drew attention to the meteorologi- 

 cal conditions of the past few days. A minimum temperature 

 on March i was succeeded by a thaw on the evening of the 2nd, 

 which was followed by a second very low temperature which 

 again gave way to a thaw on the 6th. The rise and fall of the 

 barometer corresponded to the above : the very considerable 

 double variation in atmospheric pressure was caused by a 

 minimum passing through South -West Sweden across the East 

 Sea to Russia, which was succeeded by a partial minimum 

 following the same course. Exactly similar meteorological con- 

 ditions were in existence from February 4, and were caused by a 

 minimum with its succeeding partial minimum following the 

 same course as above. Such an exact similarity of path and 

 action of two minima is of very rare occurrence, and deserves to 

 be carefully studied : on both occasions, in February and 

 March, very wintry weather was observed. — Dr. Hellman drew 

 attention to the unusually heavy snow-fall of the past winter. As 

 yet the maximum number of days on which snow falls in Berlin 

 has been fifty, but this year up to the present time it has already 

 fallen on fifty-eight days ; in the same way, until this year never 

 more than eight consecutive days of snow-fall have been observed, 

 but this winter there has been one period of sixteen consecutive 

 days on which snow has fallen. 



Stockholm. 

 Royal Academy of Sciences, March 14. — Studies on the 

 Characeae and Violse of the Isles of Gotland and Oeland, by 

 Dr. Wahlstedt. — Studies on the geographical distribution of the 

 plants in the province of Wermland, by Dr. Ringius. — On the 

 currents of disjunction, by Dr.Mebius. — On the institution of pen- 

 dulum observations in Sweden, by Prof. Rosen. — A review of the 

 Orthoptera of Scandinavia, with descriptions, by Dr. Ilaij. — 

 Analyses of gadolinite and hornilite, by Dr. W. Pettersson. — On 

 the production of nitro-cymol and its products of oxidation, by 

 Prof. Widman and Dr. Soderbaum. — On the occurrences of 

 Limnadia leiUiculaHs on the Isle of Nordkoster in the province 

 of Bohus, by Hr. Hanson. — A thunderstorm combined with water- 

 spouts near Upsala, by Hr. Th. Wigertz.— On fossil wood from 

 Egypt and Eastern Asia, by Prof. Schenk, of Leipzig. — Volcanoes 



in the interior of the north-eastern parts of Iceland, by Hr. 

 Thoroddsen, of Reykjavik. — On the determination of the constants 

 in the diurnal rotation, by Dr. Bohlin. 



Amsterdam. 



Royal Academy of Sciences, February 25. — M. Martin 

 exhibited a geological chart of the course of the River Surinam, 

 appending the communication that, during his stay in the West 

 Indies, he succeeded in discovering the geological formation in 

 which the gold occurring in those parts, and long since known 

 as wash-gold, was originally deposited. This formation is the 

 crystalline schist, a stratum in which, in Brazil also, most of 

 the gold is met with. The speaker urged that Brazil and 

 Surinam offer striking points of resemblance both in the order 

 and nature of their stratifications. — M. de Vries made a com- 

 munication on his determination of the molecular weight of 

 raffinose. His results, based upon physiological methods, tended 

 to support the formula of Loiseau and Scheibler, 



C18H3A6 + 5H2O. 

 — M. Hubrecht described the early stages in the development 

 of the blastodermic vesicle of the hedgehog. He claimed that 

 the stages observed and described by him go a long way towards 

 explaining the questionable points in the early stages of the 

 human blastodermic vesicles that have yet been noticed. 



BOOKS, PAMPHLETS, and SERIALS RECEIVED. 



Fundamental Principles of Chemistry : R. Galloway (Longmans). — Re- 

 miniscences of Foreign Travel : R. Crawford (Longmans). — An Examination, 

 of the Theory of Evolution : G. Gresswell (Williams and Norgate). — John- 

 ston's Botany Plates, IL (Johnston). — Key to the Volapiik Grammar : A. 

 KirchhofF (Sonnenschein). — Specimens of Papers set at the Army Prelimin- 

 ary Examinations, 1882-87 (Macmlllan).— Companion to the Weekly Problem 

 Papers: Rev. J. J. Milne (Macmillan). — An Indictment of Darwin: O. 

 Dawson (Freethought Publishing Company). — An Increase in the Produce 

 of the Soil through the Rational Use of Nitrogenous Manure : P. Wagner ; 

 translated by G. G. Henderson (Whittaker). — Smoke in Relation to Fogs 

 in London : Hon. Rol!o Russell. 



CONTENTS. PAGE 



The Forestry School at Cooper's Hill 529 



The Baltic Amber Coast in Prehistoric Times. By 



Arthur J. Evans 531 



Voltaic Electricity 533 



Natural History of Victoria 535 



Our Book Shelf :— 



"Technological Dictionary" 534 



"Transactions of the Sanitary Institute of Great 



I^"tain" - . . • 535 



Jordan: " Science Sketches " 535 



Letters to the Editor : — 



" Coral Formations." — T. Mellard Reade .... 535 

 "The Dispersion of Seeds and Plants." — Dr. Antonio 



J. Amadeo .535 



" Balbin's Quaternions." — Prof. W. Steadman 



Aldis 535 



Mr. Crookes and the Transformation of Heat Radia- 

 tions into Matter. — Hugh Gordon 536 



Green Colouring-matter of Decaying Wood. — Henry 



Robinson 536 



Comet a 1888 (Sawerthal).— T. W. Backhouse . . 536 

 The Hittites, with Special Reference to very Recent 



Discoveries. II. {Illustrated.) By Thomas Tyler . 536 



Elements and Meta-Elements 540 



The Duration of Life. By P. Chalmers Mitchell . . 541 



Notes 542 



Our Astronomical Column : — 



The Period of Algol 544 



Observations of Variable Stars 545 



Astronomical Phenomena for the Week 1888 



April 8-14 545 



Geographical Notes 545 



The Atoll of Diego Garcia and the Coral Forma- 

 tions of the Indian Ocean. By Prof. G. C. 



Bourne • 546 



The Royal Horticultural Society 550 



Societies and Academies 550 



Books, Pamphlets, and Serials Received 552 



