N.'l Til RE 



l/JCi-. 9, 1880 



Geological Climates 

 It was with great surprise I read Prof. Ilaughlon's unqualified 

 statement in last week's Natukk, that — "It is impoisililc to 

 suggest any rearrangement of land and water whicli shall sensibly 

 raise the kmpcyatiire of Ihc ]Vcst of Eiiyo/'c," — since I had, as I 

 thought, in my recently-published volume — "Island Life" — not 

 only "suggested" such a rearrangement, but also adduced much 

 evidence to show that it had actually occurred throughout the 

 periods when both the West of Kuiopc and the Arctic regions 

 enjoyed a much higher temperature than they do now. 1 will 

 now briefly re-state my "suggestion," and will also make a few 

 remarks on the general causes of difference of temperature, which 

 may serve to render the subject more intelligible. 



U is now well known that jilaces in tlic temperate zones owe 

 tlicir temperature at dinfercnt seasons only partially to the 

 amount of direct sun-heat they receive, but very largely to the 

 amounts of heat brought to them by currents of air. Thus we 

 explain, not only the mild winter climate of our islands as due to 

 the prevalence of westerly and south-westerly winds which have 

 become warmed by jiassing over the Atlantic, but also the 

 ■wonderful inequality of temperature at different seasons of the 

 year. When we have warm sjiringlike days in mid-winter, it is 

 i)ccause these warm currenls of air are passing steadily over our 

 islands ; while continued hard frosts are as clcarlydue to masses 

 of cold air from the north or north-east which drift down to us, 

 often with no perceptible wind. Again, when in April and 

 May we have da)-3 as cold as those of December and January, 

 they can always be traced to northerly or easterly currents of air, 

 and are probably often connected with tlie southern drift of the 

 icebergs at that season. It is clear then, that if south-westerly 

 winds were to continue throughout the winter, the severity of 

 that season would be entirely abolished ; and the same effect 

 would be produced if by any means the winds from thi north 

 and east lost their severity. 



Now the source of the constant warmth of our v^■esterIy winds 

 is adniilled to be the influx of warm w.ater into the North 

 Atlantic — chielly by the Gulf Stream ; and this warm northward 

 tlow of trojncal water, being primarily due to the trade-winds, 

 is not confined to the Allanlic, but is equally present in the 

 other great oceans, and similar effects are produced in them, 

 though nowhere to so great a degree as in our islands, owing to 

 our insular position and the great extent to which Europe to 

 (lie east of us is permeated by water as compared with North 

 America or Asia. The North Pacific, with its great Japan 

 current, is probalily quite as warm as the North Atlantic; but 

 Vancouver s Island, though further south than London, has not 

 so mild a climate ; and this can bj clearly traced to the great 

 mass of land to the east and north of it, the lofty snow-clad 

 moanlains, and the absence of those deep gulfs and inland seas 

 which do so much to ameliorate the climate of Europe. 



Prof. Ilaughton states, in his "Lectures on Pliysical Geo- 

 graphy," that the Kuro Siwo, or great Pacific current, is two and 

 a half limes as large as the Gulf Stream, while the Mozambique 

 current, which forms the outflow of the warm waters of the 

 Indian Ocean, is one and a half times as much, so that these 

 two currents have together four times the bulk and heating 

 power of the Gulf Stream. If therefore those two^currents at any 

 time obtained an entrance into the Arctic Ocean, it is difficult 

 to over-estimate their effect on its climate. The Gulf Stream, 

 of which proljably not half passes northwards of our islands, 

 gi\'cs to Iceland tlie same winter tem[>erature as Philadelphia, 

 and keeps the North Cape (far within the Arctic circle) perma- 

 nently free from ice, and this, notwithstanding the powerful 

 counter.acting inllucnces of the lofty Scandinavian mountains on 

 the one side, and the huge ice-clad plateau of Greenland on the 

 other. Sii)ipose that only an equal proportion of the luiro 

 Siwo enloicd the Arctic Ocean, is it not probable that no sea- 

 ice at all would form there? While, if Greenland were less 

 elevated and thus ceased to be an accumulator of ice, the com- 

 bined cflect might l>c to render the w hole Polar area free of 

 icebergs. Tliis would at once tlo away with the chief source of 

 winter cold to all north temperate lands, and ameliorate the 

 climate of America as much, proportionately, as that of Europe. 

 Jint wo have yet to consider a still more powerful agent in 

 ameliorating the climate of Western Europe in Secondary and 

 early Tertiary times. The heated w aters of the Indian Ocean 

 have now no northern outlet, and only jienetrate the continent 

 in the sub-tropical Red Sea and Persian Gulf. Now if we sup- 

 pose the waters of the Bay of Beng.il and the Arabian Sea to 

 have h.ad northward outlets throuah the heart of the Euro-Asiatic 



continent, penetrating in two or more directions into the then 

 much more extensive Arctic Ocean, we should have an agency at 

 work which would render the presence of any permanent ice in 

 the North Polar area as impossible as it is now in Scotland. 

 The cooling agency of ice being once abolished, the compara- 

 tively small area of the Polar .as compared with the Tropical 

 seas (about one-tenth) would facilitate the raising of the tem- 

 )icrature of the former to perhaps 15" or 20° F. above the freezing 

 point, and this would not only give the Arctic low lands a climate 

 c[uite sufficient for the vegetation which we know they supported, 

 but, by doing aw.iy with the only source of our winter cold, 

 would give our islands a perfect immunity from frosts and render 

 them capable of supporting the vegetation now characteristic ol 

 sub-tropical lands. 



Tiiat the modifications of land and sea here indicated tiid exist 

 throughout a considerable portion of past geological ages, and 

 that the existing consolidation of the gre.it northern continents, to 

 which the possibility of our present Arctic climates is mainly 

 due, is a comparatively recent and abnormal phenomenon, I have 

 endeavoured to prove in the work already referred to. At 

 present I have only undertaken to show, that a "suggested" re- 

 arrangement of land and water adequate to raise the temperature 

 of Western Europe to a very sciisililc, or even to a very large 

 extent, is "possible." ALrUED R. WALLACE 



Photophonic Music 

 I HAVE not yet met with any reference to the capabilities of 

 the photophone for giving musical harmonies. Might not some 

 curious effects be got in some such way as this : — Suppose a disk 

 perforated ^^•ith holes in four concentric circles corresponding to 

 the notes of a chord ; a beam of light to be sent through each 

 circle to a lens and disk of rubber with tube (as Prof. Bell has 

 described), the four tubes debouching in a cup-shaped cavity to 

 be applied to the ear ; lastly, the disk to be rotated variably by 

 means of a small windmill or other ivise. Another arrangemeut 

 might be to make the beams cf light p.ass through the holes to 

 selenium cells in four telephone circuits, the four telephones 

 being placed in one frame, against which the listener's ear w-ould 

 be put, or coupled in pairs, one pair jnit to either ear. Again, 

 might not harmonised tunes be obtained thus : — Suppose a 

 broad open drum of wood or cardboard rotated uniformly on 

 a screw forming a vertical axis. The drum is perforated in a 

 spiral band of four lines of holes (for the light), corresponding to 

 the notes of the harmonised air to be produced. This spiral 

 band passes before four rubber disks or selenium cells (.is in the 

 former system), but arranged vertically and placed within the 

 drum, at the lower part. The drum, it will be understood, 

 works gr.idually down the axis, presenting a continuous four-line 

 series of holes before the receiving apparatus. Again, a long 

 continuous strip of cardl)oard, with four rows of holes, might be 

 IKissed before the receiver in any convenient \v.iy. M. 



The " Philosophy of Language " 



Though it is my principle never to answ'er any criticism of 

 my writings, I find myself obliged to deviate for once from this 

 rule by the char.icler of your highly esteemed review, and by 

 the desire to find a discerning appreciation from your readers, 

 whose judgment has for me the greater value, as it is the main 

 aim of all my works to restore the relations between the science 

 of mind and natural philosophy. Therefore you would oblige 

 me very much by publishing the following short remarks : — 



The critic of my brochure (" Max Midler and the Philosophy 

 of Language,") says, "... Nor is speech the deliberate product 

 of a conscious will." Now it is the real aim of all my works 

 on the philosophy of language to show how the human will — 

 before dark and unconscious — grows to consciousness ly /a)t- 

 !;iM^o and human activity intimately connected with it. Can 

 there be the least doubt of this, even if I refer only to the 

 motto of my "Origin of L.mguage,'' — "Language has created 

 reason, before language man was without reason " ? 



Vour critic has made me s.iyyHx/ the coiitrary o/what I really 

 have saiJ. Besides, it would have been only fair if the critic 

 had ]winted to the following little passage of my brochure : — 



"Max MiiUer has since expressed his full assent to this 

 view," (vi/.., my theory of the origin of language). 



Mayence, November 11 Ludwig NoiRfi 



[I gladly accept the author's assurance that he adheres to the 

 view that "language has created reason." At the same time his 



