1 66 



NA TURE 



\ytme 1 6, 1887 



discuss the views of Dr. Croll on the date of the Glacial epoch. 

 Dr Croll who had at first referred this to an earlier phase 

 of orbital 'eccentricity, commencing 980,000 years ago, subse- 

 quently rec^arded it as coinciding with a minor period of eccen- 

 tricity that" commenced 240,000 and terminated 80,000 years 

 since This last estimate was chiefly supported by the amount 

 of denudation that had subsequently taken place. The efficacy 

 of the increased eccentricity of the earth's orbit in producing the 

 cold of the Glacial epoch was shown to be very doubtful ; for as 

 similar changes in the eccentricity had occurred 165 times in 

 the last 100 millions of years, there must have been many 

 glacial epochs in geological time, several of them much more 

 severe than that of the Pleistocene"period. But of such glacial 

 epochs there was no valid evidence. Another inference from 

 Dr. Croll's theories, that each glacial epoch consisted of a suc- 

 cession of alternating cold and warm or interglacial phases, %yas 

 also questioned, such alternations as had been indicated having 

 probably been due to changes in the distribution of land and 

 water, not to cosmical causes. The time requisite for such inter- 

 glacial periods as were supported by geological evidence was 

 more probably hundreds than thousands of years. Recent 

 observations in Greenland by Prof. Helland, Mr. V. Steenstrup, 

 and Dr. Rink, had shown that the movement of ice in large 

 quantities was much more rapid, and consequently the denu- 

 dation produced much greater than was formeriy supposed. The 

 average rate of progress in several of the large iceberg-pro- 

 ducing glaciers in Greenland had been found to be 36 feet daily. 

 Applying these data and the probable accumulation of ice due to 

 the rainfall and condensation to the determination of the time 

 necessary for the formation of the ice-sheet, the author was dis- 

 posed to limit the duration of the Glacial epoch to from 15,000 

 to 20,000 years, including in this estimate the time during which 

 the cold was increasing, or preglacial time, and that during which 

 the cold was diminishing, or postglacial time. Details were then 

 given to show that the estimate of i foot on an average being 

 removed from the surface by denudation in 6000 years, on which 

 estimate was founded the hypothesis of 80,000 years having 

 elapsed since the Glacial epoch, was insufficient, as a somewhat 

 heavier rainfall and the disintegrating effects of frost would pro- 

 duce far more rapid denudation. It was incredible that man 

 should have remained physically unchanged throughout so long a 

 period. At the same time, the evidence brought forward by Mr. 

 Tiddeman, Dr. Hicks, and Mr. Skertchly of the occurrence of 

 human relics in preglacial times, had led the author to change 

 his views as to the age of the high-level gravels in the Somme, 

 Seine, Thames, and Avon valleys, and he was now disposed to 

 assign these beds to the early part of the Glacial epoch, when 

 the ice-sheet was advancing. This advance drove the men who 

 then inhabited Western Europe to localities such as those men- 

 tioned which were not covered with ice. Man must, however, 

 have occupied the country but a short time before the land was 

 overwhelmed by the ice-sheet. The close of the Glacial epoch, 

 i.e. the final melting of the ice- sheet, might have taken place 

 from 8000 to 10,000 years since. Neolithic man made his 

 appearance in Europe 3000 to 4000 years B.C., but may have 

 existed for a long time previously in the east, as in Egypt and 

 Asia Minor civilized communities and large States flourished at 

 an earlier date than 4000 B.C. After the reading of the paper 

 there was a discussion, in which the President, Dr. Evans, Dr. 

 Geikie, Prof. Boyd Dawkins, Dr. Plicks, and others took part. 

 — Notes on some Carboniferous species of Murchisonia in our 

 public mupeums, by Miss Jane Donald. Communicated by 

 Mr. J. G. Goodchild. 



Zoological Society, June 7. — Mr. E. W. H. Holdsworth, 

 in the chair, — The Secretary read a report on the additions that 

 had been made to the Society's Menagerie during the month of 

 May, and called attention to a Tooth -billed Pigeon {DiduncuUis 

 strigirostris) brought home from the Samoan Islands, and pre- 

 sented to the Society by Mr. Wilfred Powell ; to two Red- 

 spotted Lizards [Eremias rubro- punctata) obtained at Moses' 

 Well, in the Peninsula of Sinai, and presented to the Society by 

 Mr. G. Wigan ; and to a small scarlet Tree- Frog {Dcndrobates 

 typographus) from Costa Rica, presented to the Society by Mr. 

 C. H. Blomefield. — Mr. Sclater called attention to examples of 

 two North American Foxes now living in the Society's Gardens, 

 which he referred to Canis velox and C. vir^niantis. — A com- 

 munication was read from Mr. A. O. Hume, containing some notes 

 on Btidorcas taxicolor, the Gnu-goat or Takin of the Mishmee 

 Hills, and some remarks on the question of the form of the horns 

 in the female of this animal. — A communication was read from 



Mr. E. Symonds, containing notes on various species of Snakes 

 met with in the vicinity of Krounstadt, Orange Free State, 

 specimens of which had been forwarded to Mr. J. H. Gurney, 

 and determined by Dr. Giinther. — Mr. Martin Jacoby, gave an 

 account of a small collection of Coleoptera obtained by Mr. W. 

 L. Sclater in British Guiana. — Prof G. B. Howes, read a paper 

 on a hitherto unrecognized feature in the larynx of the Anurous 

 Amphibians. This was the existence in many individuals of 

 various species of a rudimentary structure, which appeared to 

 correspond to the epiglottis of Mammals, and which in some 

 instances attained a remarkable development as an organ of voice. 



Institution of Civil Engineers, June 7. — Annual General 

 Meeting. — Mr. Woods, President, in the chair. — The Report of 

 the Council on the condition of the Institution, and the annual 

 statement of the accounts, were received. The number ot 

 members on the roll of the Institution, on March 31, 1887, was 

 4347, of whom 20 were honorary members, 1568 member-, 2275 

 associate members, and 484 associates. This was a net increase 

 of 173, or 419 per cent., on the 4174 members of all classes 

 recorded last year. The elections had included 34 members, 

 234 associate members, and 6 associates, while the deaths, 

 resignations, and erasures were 106. Many deaths had occurred 

 among the older members of the Institution during the past 

 twelve months, chief among whom must be placed Sir Joseph 

 Whitworth, whose world-wide renown as a mechanician it was 

 unnecessary to dwell upon. By his will he bequeathed to the 

 Institution 80 shares, of £2'^ each, in the firm of Sir Joseph 

 Whitworth and Company, Limited. During the twelve months 

 under review, 2H candidates were admitted as students. On 

 the other hand, 82 were elected into the corporation as associate 

 members, and ro6 ceased, from various causes, to belong to the 

 class. The total number of students on March 31 last was 949, 

 as against 926 at the same date in 1886. There were twenty-six 

 ordinary meetings during the session, when twenty original 

 communications were read and discussed. The Howard Quin- 

 quennial Prize had been adjudged to Dr. John Percy, in recog- 

 nition of his researches on the uses and properties of iron. To 

 the authors of some of the papers read and discussed at the 

 ordinary meetings medals and premiums had been awarded, 

 viz. : Telford Medals and Telford Premiums to Alexander B. 

 W. Kennedy, Dr. J. Hopkinson, Colonel E. Maitland, and W. 

 Willcocks ; a Watt Medal and a Telford Premium to E. A. 

 Clowes ; Telford Premiums to W. J. Dibdin, W. S. Crimp, 

 J. J. Webster, and J. Kyle ; and the Manby Premium to L. H. 

 Ransome. For papers printed in Section II. of the Proceedings, 

 without having been publicly discussed, the following awards 

 had been made : a Telford Medal and a Telford Premium to 

 J. G. Gamble ; a Watt Medal and a Telford Premium to W. J. 

 Last, and Telford Premiums to J. Hetherington, K. W. Hedges, 

 C. J. Wood, A. Leslie, and D. A. Stevenson. Twelve students" 

 meetings had been held on alternate Friday evenings, at which 

 thirteen papers were read and discussed. — The ballot for Council 

 resulted in the election of Mr. G. B. Bruce, as President ; of 

 Sir John Coode, Mr. G. Berkley, Mr. H. Hayter, and Mr. A. 

 Giles, M.P., as Vice-Presidents; and of Mr. W. Anderson, 

 Mr. B. Baker, Mr. J. W. Barry, Sir Henry Bessemer, F.R.S., 

 Mr. E. A. Cowper, Sir James N. Douglass, Sir Douglas Fox, 

 Mr. C. Hawksley, Mr. J. Mansergh, Mr. W. H. Preece, 

 F.R.S., Sir Robert Rawlinson, C.B., Sir E. J. Reed, K.C.B., 

 F.R.S., M.P., Mr. W. Shelford, Mr. F. C. Stileman, and Sir 

 William Thomson, F. R.S., as other Members of Council. 



Chemical Society, June 2, — Mr. William Crookes, F.R.S., 

 President, in the chair. — The following papers were read : — 

 The equivalent of zinc, by Lieut. -Colonel Reynolds, late R.E., 

 and Prof. W. Ramsay. — The magnetic rotation produced by 

 chloral, chloral hydrate, and hydrated aldehyde, by Dr. W. H. 

 Perkin, F.R.S. — Note on a new class of voltaic combinations 

 in which oxidizable metals are replaced by alterable solutions, 

 by Dr. C. R. Alder Wright and Mr. C. Thompson. It 

 appeared to the authors probable that just as a liquid capable of 

 parting with oxygen, chlorine, &c., can be used in conjunction 

 with an electrode of unchangeable material at one side of a 

 voltaic cell (as in Grove's nitric acid battery and analagous com- 

 binations), or may be replaced by a solid conducting electrode, 

 itself capable of losing oxygen (e.g. a plate of strongly com- 

 pressed peroxide of lead), so conversely might a conducting 

 plate of oxidizable material [e.g. zinc) at the other side be 

 replaced by an unchangeable electrode in conjunction with a 

 liquid capable of taking up oxygen, chlorine, &c. , without pro- 

 ducing any fundamental change in the character of the actions 



