4i8 



NATURE 



{March 25, 1875 



air at various health-resorts. — On the annual means of thirteen 

 years' observations at London, by Mr. Richard Strachan. The 

 author, having already read a series of papers on the different 

 seasons, now gives a summary of the results for the thirteen years. 

 The mean annual value for pressure from observations made at 9 

 A.M. is 29*958 inches; themean temperature of the air at the same 

 hour, 49°'6 ; the annual amount of rain, 24 '2 inches; the number 

 of rainy days, 165 ; the resultant direction of the vrind, S. 84° W., 

 and its force 0'95. The author concludes as follows :— On the 

 whole it seems that excess of pressure accompanies deficiency of 

 rainfall, slow translation of the air fiom the north of west, and 

 fair weather. Deficiency of pressure accompanies excess of rain- 

 fall, rapid translation of air from the south of west, and foul 

 weather. If meteorological science could give prescience of the 

 annual value of any one of the elements, the others could be 

 predicted with considerable accuracy. 



Geologists' Association, March 5. — W. Carruthers, F.R.S., 

 president, in the chair. — On the relative age of some valleys in 

 the north and south of England, and of the various Glacial and 

 Post-glacial deposits occurring in them, by C. E. De Ranee, 

 E.G. S. The application of geology to agriculture and medical 

 science caused the -want of an exact knowledge of the various 

 superficial deposits, which lie scattered over the country, to be 

 felt, and led the late Sir I-'.oderick Murchison to direct the 

 Government Geological Sui-vey in future to prepare a drift 

 edition of each map, showing the actual deposit at the surface. 

 The publication of such maps of the lower Thames valley 

 and of South Lancashire enabled the author to compare the 

 sequence of deposits in these two important districts, and the 

 results arrived at, with the sequence exhibited in other areas. 

 In Lancashire the Glacial Drift deposits attain a thickness of 

 200, and in one instance of 400 feet, and the valleys of Uie 

 Ribble, Irwell, and Mersey were shown to have been exca- 

 vated in these deposits by the denuding action of these rivers 

 in Post-glacial times, which, as they gradually cut their val- 

 leys lower and lower, left wide and extensive terraces of river 

 gravels on the slopes above ; Manchester, and the villages 

 between it and AUrincham, being built on one of these terraces. 

 Of still newer date is the alluvial plain beneath the terraces, 

 which is made of loam, peat, and river gravel. The peat was 

 shown to be connected with the great peat mosses of West Lan- 

 cashire, where it reaches 30 feet in thickness, and was correlated 

 with the peat beds and submerged forests found beneath the sea- 

 level, around the entire coasts of the British Isles and the North 

 of France. Beneath the peat in the West Lancashire plains 

 occuiTed the Presall marine gravel, \\hich was correlated with 

 the Burth beds of Somersetshire, the raised beaches of Sussex, 

 of the Isles of Wight and Portland, and of Cornwall ; also with 

 the fluviatile gravel lying beneath the peat horizon, in the Lanca- 

 shire valley alluvial plains, and in the tin-bearing gravels of 

 Cornwall. The subsidence marked by the marine beds, and 

 subsequent elevation, during the forest continental era, followed 

 by a subsidence to existing levels, took place after the rivers had 

 cut down their valleys to their present depth, with few excep- 

 tions. Neolithic man entering the country durmg the forest era. 

 The far older terraces on the valley slopes were compared with 

 the implement-bearing gravels of the Post-glacial valley of the 

 Ouse at Bedford, and with similar ancient high-level gravels 

 in the Thames, the Hampshire Basin, the Somme, and the 

 Seine near Paris, where no Glacial deposits occur, and it 

 was argued, that regarding the similar relation to the depth of 

 the valleys excavated, to the drainage area, and the position of 

 the implement-bearing high-level gravels — that these, like the 

 terraces of gravels of Lancashire without implements, and those 

 of Bedfordshire with, were alike of Post-glacial date. In the 

 Pre-glacial continental era the Thames flowed in a similar direc- 

 tion to the existing liver, but 100 feet above its present 

 level, its course nearly defining the southern limit of the subse- 

 quent Glacial sea, under which the Weald of Kent and Sussex 

 was never submerged. In Post-glacial times the Thames may 

 have denuded the southern edge of the Glacial deposits, when it 

 commenced to cut down its present valley and to deposit its 

 oldest and higher river gravels, which are immediately overhung 

 by the Glacial beds. The valley appears to have attained its 

 greatest depth in the era immediately preceding the subsidence 

 that occurred prior to the great peat and forest period, the bottom 

 of the valley east of London being considerably lower than the 

 bed of the present stream, but the level is not sufficiently low to 

 lead to the belief that any streams that may have flowed from 

 the watershed of the Weald anticlinal, through what is now the 



I 



Straits of Dover, to the prolongation of the Thames, would have 

 cut sufficiently deep to have produced fissures that might have 

 been fatal to either of the proposed lines of the Channel Tunnel. 



Royal Horticultural Society, March 9. — Adjourned Annual H 

 Meeting. — Viscount Bury in the chair. — The Chairman moved 

 the adoption of the amended report of the Council. The pro- 

 posal of Messrs. Prince to construct a skating-rink, and to pay 

 a rent equal to 1,100/. a year, had fallen through owing to 

 II.M. Commissioners (without whose consent the Society had 

 no power to underlet any portion of its premises) having deemed 

 it inexpedient to grant then: consent. The report alsj 

 pointed out that "the ordinary income of the Society cannot 

 support its present expenditure," and that "unless the rent of 

 2,400/. is paid to H.M. Commissioners next year the lease of the 

 South Kensington Gardens may be forfeited, and to prevent this 

 contingency an increased revenue must lie obtained." — The 

 Chairman announced that since the adjourned meeting, two 

 members of Council, Sir A. Slade, Bart., and Mr. Chetwynd, 

 had resigned, and the legal advisers of the Society had advisee 

 them that these vacancies must be filled by the Council, and noi 

 by the Eellows. In the interval, also, a despatch had been 

 received from H.M. Commissioners, stating that they regarded 

 the legal status of the Council as now free from objection, and 

 were ready to resume official relations with it. — After some dis- 

 cussion, the amended report was unanimously adopted, and the 

 Council havmg promised to summon a geneial meeting to con- 

 sider the present position of the Society, the meeting adjourned. 

 Victoria (Philosophical) Institute, March 15. — C. Brooke, 

 F.R.S., in the chair. — Rev. J. McCann, D.D., read a paper 

 on the nature and character of evidence for scientific purposes. 

 He commenced by stating that the mind could alone gain scien- 

 tific knowledge by the process of generalisation. This must be 

 based on evidence that was sufficient, and such as warranted the 

 inferences drawn from it. The nature of evidence was then 

 examined, and the difficulty, but necessity, of correct observation 

 and logical reasoning from this, in order to form a sound hypo- 

 thesis, was shown. Various points in Prof. Tyndall's address 

 were criticised, 



Glasgow 

 Geological Society, March 11. — Mr. John Young, F.G.S., 

 vice-president, in the chair. — The following papers were read : — 

 Notes on a tract of vertical trees in carboniferous strata ; and 

 on river debris found in sandstone, by Wm. Grossart, Salzburg. 

 In his first paper, the author described a number of trees wluch 

 had been found in a pit, 40 fathoms in depth, lately sunk to the 

 " Little Drumgray " coal in the west end of Shotts parish. 

 This coal is of an average thickness of 22 inches, and is over- 

 laid . by a compact sandstone of from two to five fathoms in 

 thickness, with a few inches of grey shale, seldom exceeding a 

 foot, separating the coal from the sandstone above. In the 

 workings of the mine eight erect tree-trunks had been brought 

 to light, all resting on the coal-bed, and disappearing in the 

 shale forming the roof of the mine ; but there had been no 

 opportunity of observing if they entered the sandstone above. 

 The usual organic markings found on similar remains were 

 absent, so that it was impossible to determine precisely to what 

 genus they belonged. In his second paper. Dr. Grossart de- 

 scribed a series of beds overlying the ' ' Virtue Well " coal in his 

 neighbourhood, the uppermost being a sandstone, 60 feet in 

 thickness. Below this is a gritstone bed, two feet in thickness, 

 containing rounded and angular pieces of quartz embedded in 

 sand, also remains of trees, pieces of black shale, and gas coal. 

 This is succeeded by a thin shale bed, then by a laminated 

 sandstone ten feet in thickness, followed by a black shale resting 

 on the coal. From a review of the whole series, the author 

 concluded that the beds under consideration were formed at the 

 mouth of a river flowing from east to west at a period posterior 

 to the formation of the Virtue Well coal. 



Manchester 



Literary and Philosophical Society, Jan. i8.— Mr. John 

 Barrow in the chair. — Mr. James Cosmo Melvill, F. L.S., read 

 a paper on the botany of Wilmington, North Carolina, with an 

 especial reference to the habitat of Dioncca muscipula, Ellis. 



Feb. 15. — Mr. Charles Bailey in the chair. — Mr. Rogers ex- 

 hibited a specimen of Carex ornithopoda, Willd., collected by 

 Mr. J. Wliitehead in Millersdale, Derbyshire, in July of las* 

 year.— Mr. Sidebotham, F.R.A.S., then read a paper, entitled, 

 "Notes on the Botany and Natural History of Tenby and the 



