April 14, 1887] 



NATURE 



555 



gravels round Ealing-. Notwithstanding this, however, 

 hardly any addition was made to London implements 

 for some years, when Mr. Wonhington Smith developed 

 the marvellous faculty of finding them in nearly 

 every gravel-pit he went into. Our author makes a 

 good third to these two, and that is saying a great deal. 

 It is to be hoped that his book may lead other 

 observers to join in the work that he has so much ad- 

 vanced, and to do for other parts of London and the 

 surrounding country what he and the above-named 

 authors have done on the north-west and north-east, and 

 Mr. F. Spurrell on the south-east. 



The antiquity of man is so controversial a subject that 

 anyone who writes on it must expect to find more foes 

 than friends. Mr. Brown, therefore, must not be surprised 

 at e.xception being taken to some of his views, and in 

 noticing his work one may fairly point out some matters 

 on which opinions are likely to difter. 



The remark, on p. 13, of piles (for dwellings) having 

 been found at Moorfields received a curious illustration 

 whilst it was in the press ; for a building in that district 

 was then being underpinned, on account of part of the 

 pile-structure 'on which it was based having decayed ; 

 that building being none other than the lecture-hall of 

 the London Institution. 



The name "chalky boulder clay" was given by Mr. S. 

 v. Wood, Jun., and not by Mr. Skertchly, as the foot, 

 note on p. 27 says. 



That the brick-earths of Erith, Crayford, &c., are pre- 

 glacial few geologists will be found to believe ; perhaps, 

 indeed, only Prof Dawkins ; and our author wisely throws 

 the burden of this belief on th.it gentleman[(p. 33). :, 



As to the Tilbury man, alluded to on p. 42, there can be 

 no doubt that his remains were found in a very late post- 

 glacial deposit, simply the alluvium of the Thames. Mr. 

 T. V. Holmes has set this question at rest (Trans. Essex 

 Soc). 



By a slip, on p. 45, hard chalk, flint, and greywethers 

 have been classed amongst rocks that do not occur in the 

 valley of the Thames. 



Probably there are geologists who would be disposed 

 to question the strictly glacial origin of the furrowed 

 gravel and the bent loam carefully described on pp. 45-47. 

 Such irregular surface-deposits are so common in districts 

 far from undoubted glacial beds as to leave their origin 

 doubtful. 



" The large encroachments of the sea which have taken 

 place ... in historic times " are no proof of depression 

 (p. 4S). They are simply the result of denudation along 

 coasts. 



The term " alluvium " should be confined to the deposits 

 of rivers and not applied generally to surface-soil, as on 

 p. 50, in which case it becomes a useless synonym. 



The peculiar black bands often seen in gravels have 

 troubled many observers, but from finding particles of 

 carbonised wood occasionally in them .Mr. Brown is not 

 justified in saying that " there seems to be no doubt that 

 such black strata are due to vegetable life," especially as 

 he recognises the fact that the colour (which is what he 

 refers to) is generally due to oxide of iron or of man- 

 ganese. And even were the blackness due to vegetation, 

 it is by no means a reasonable assumption that the beds 

 were land-surfaces (p. 54), for the vegetable remains may 



have been carried down by water. That the white beds 

 occasionally seen are " probably the result of decomposi- 

 tion of animal or vegetable matter" is also rather doubt- 

 ful, the colour (which here again is what the author refers 

 to, though his language implies the beds themselves) being 

 often the result simply of the washing-out of the iron- 

 oxide, which gives the usual brown tint, by percolating 

 water. 



There may be some doubt whether, when man first 

 invaded England, the connexion of our country with the 

 mainland was caused " by the uprise of the bottom of 

 what is now the . . . North Sea." The present severance 

 need not have been brought about by depression, but 

 perhaps is owing simply to denudation, so that there 

 is no need to invoke uprise to account for former con- 

 nexion. There is also some difficulty in the uprise in 

 question, as Mr. Brown thinks that Middlesex, &c., "was 

 slowly emerging from the sea," and therefore must have 

 been at a lower level than now. It is most likely indeed 

 that at that time the whole land was higher than now, 

 as otherwise it would be hard to account for the greater 

 size of the rivers, as compared with their present descend- 

 ants, for higher land would give greater rainfall, and 

 greater rainfall means stronger streams. If " man beheld 

 the land now under the 300-foot contour in Middlesex as 

 an arm of the sea," there could have been nothing worthy 

 the name of river, or even of brook, in the county, and 

 the deposition of such coarse matter as our river-gravels 

 would be out of the question (pp. 67, 68), those gravels 

 certainly not being marine deposits. 



In the picture of a Pateolithic scene from Castlebar 

 Hill (pp. 185, &c.), it w'ould seem as if the author were, as 

 is often the case with geologists, a little too much im- 

 pressed with the present features of the country, so as to 

 allow too little for the amount of denudation that has 

 happened since the time his picture represents. Instead 

 of water then occurring over the whole of the low clay- 

 country to the north, is it not possible that the tract in 

 question was much higher than now, a great sheet of 

 clay having been gradually swept off it since ? Indeed, 

 the author distinctly recognises the great amount of 

 denudation that has occurred south of Castlebar Hill, 

 along the valley of the Thames (pp. 191, 192), and of 

 course there is no possibility of the process being confined 

 to one side of the ridge. 



The conclusions of Dr. Hicks as to the Glacial or pre- 

 Glacial age of man in North Wales, noticed at the end of 

 the work, are not altogether accepted, and should be con- 

 sidered as still waiting for the verdict of geologists. 



Mr. Brown is clearly a positivist, as far as worked flints 

 are concerned, and one is tempted to speculate on his 

 direct descent from Pateolithic ancestors, for, as if by 

 some hereditary instinct, he is enabled to be quite 

 positive as to the uses to which sundry implements have 

 been put, to an extent, indeed, to which probably few of 

 even that highly imaginative class of men, antiquaries, 

 will follow him. Some examples of this positivism may 

 be noticed. Thus certain flakes were " evidently intended 

 for spear-heads " (p. 58) ; and certain " triangular stones 

 . . . could hardly have been intended for use in any other 

 way " than as arrow-heads, " they were no doubt hafted " 

 (p. 117); but froin the figures given of some of these 

 i stones one would be inclined to regard them as little else 



