NA TURE 



\ATov. 12, 1874 



groups into which they were divided. The independence of 

 teachers will, by these new regulations, be greatly increased ; for 

 they will no longer be compelled to hurry as rapidly as possiljile 

 over the elements of various branches of physics, but will be free 

 to teach certain portions of the subject with greater thorough- 

 ness, and will secure at the same time for their pupils a better 

 chance of passing. Tlius, supposing the questions to be equally 

 apportioned, a candidate fairly acquainted with tlie elements of 

 mechanics only would have no difficulty in succeeding. 



The examinations lor the Science degree are at present under 

 the consideration of the Senate, and we may hope, therefore, 

 that before lonj; many of Prof. Foster's grounds of complaint 

 will have been removed. 



London, Nov. 9 ruiLiP Magnus 



Gresham Lectures 



In N.'iTURE, vol. xi. p. 2, appeared a very just and interesting 

 article on the Gresham Lectures. I wish to endorse the opinion 

 therein expressed of the misapplication of that institution. 



Last Friday evening, at tv/enty minutes past seven, I entered 

 Gresham College from cuiiosity. The two superb beadles to 

 whom you allude were seated in the hall in all the glory of 

 official gold lace. I walked into the lecture theatre, whicli to 

 my surprise was more than half filled. A jerky lecturer in 

 scarlet silk M.D. robes was unfolding the mysteries of sound. 

 He was explaining tliat sound consisted of vibrations like those 

 of ligkl. lie said that the lowest note appreciable to human 

 ears was produced by 16, the highest by 24,000 vibrations per 

 second. Prompted liy his assistant (in whom I recognised the 

 professor of chemistry at one of our metropolitan hospitals, and 

 a talented lecturer), he said the velocity of sound was 1, 125 feet 

 per second, but did not allude to the variations in the same 

 medium under different conditions of temperature and pressure. 

 Light, he said, travelled 135,000 miles per second. He probably 

 mistook an 8 for a 3 in the book from which he obtained his 

 information. Tlie velocity of sound in water, he said, had been 

 determined by an English gentleman, who fixed a bell in a boat 

 at one side of the Lake of Geneva and stayed on the other side 

 himself ; then he set tlie bell ringing by electricity, and plunged 

 his head under the water at the same instant ! This lucid ex- 

 planation was received with all the seriousness with which it was 

 delivered. He proceeded to explain the human voice, which he 

 said resembled the harmonium ; and he showed what he meant 

 by the harmonium, namely, a small Imrmoiiica, or instrument in 

 which plates of glass suspended on tapes are struck witli a 

 hammer consisting of a piece of cork on a whalebone. This 

 information was also received with self-satisfied gullibility. 

 Choking with indignation, I left the building, never having heard 

 in all my life, either in sermon or lecture, so many false statements 

 publicly uttered in the space of half ,in hour. 



I am no physicist myself, but the fact that I have heard such 

 men as Tjndall, and s=en such experimenters as Frankland and 

 Guthrie, probably accounts for my non-appreciation of the 

 Gresham lecturer, who I understand is a classical scholar — cela 

 s'explique. Maurice Lichtenstein 



Clyde Wharf Sugar Refinery, Nov. 8 



Insects and Colour in Flowers 



The true Darwinian answer to my letter in Nature, vol. x. 

 p. 503, has been fairly given by Mr. Boulger and Mr. Comber 

 (vol. x. p. 520) ; but if that answer h.ad ajipeared to me to be 

 sufficient, the letter would not have been written. 



Mr. Boulger correctly attributes t) me the opinion that the 

 development of beauty is an " object in nature." He thinks it a 

 fallacious opinion : so I suppose does Mr. Darwin. I hold that 

 opinion advisedly, however, and believe that the rejection of it is 

 a constant source of error in Mr. D.arwin's bonks, for which 

 oiherwise I have the profoundest respect and admiration. 



I do not dispute that colour may be attractive to insects, or 

 that the reproduction of plants may be assisted by it ; but I 

 reject the doctrine that the colour would have no raison if tire if 

 insects were exterminated, and I believe that Mr. Darwin's 

 theories upon this point are not sufficient to explain his own 

 facts, or such other facts as are revealed by Mr. Comber's curious 

 researches into the dispersion of coloured flowers. 



I do not see any reason to doubt that if all flowering plants 

 had been propagated by buds and stolons only, as sonie plant; 



practically are, the world at this epoch would still have known the 

 beauty of flowers, although probably with less variety of form 

 and c ilour. It is pait of the nitur.rl development of the wave of 

 Ufe, as sure to b; produced when the total conditions are ripe for 

 it, as leaves in the spring, or as lycopods in the coal-age and 

 cjnilers in the oolite. 



Tlie law of natural selection expresses truly enough the inter- 

 action of forces in the great heaving life-sea, but the forces are 

 not increased or diminished by it, only modified in their lines of 

 motion, the course made clear for one and obstructed for 

 another ; here a union of similars, and there a neutralisation of 

 opposites ; while each works out a destiny of its own as an indi- 

 vidual wave, and shares the co nmon destiny of some larger wave 

 of which it is a constituent pait. 



What insects do in relation to the colour of flowers is to 

 modify the conditions, so that the force, which has already begun 

 to show its tendency to develop colour, may get freer play, and 

 in each generation approach nearer to its climax. 



The many ins'iances in which colour is developed indepen- 

 dently of insects seem to me to show quite conclusively that the 

 colour-producing force which exists in the plant will break 

 through all obstructions whenever the opportunity is presented. 

 Sometimes increased richness of soil will furnish the necessary 

 condition ; sometimes a higher temperature ; sometimes cross- 

 fertilisation ; sometimes the care and selection of man. 



This law hold; good throughout the organic world, and 

 accounts for colour wherever it is found. The Darwinian doc- 

 trine of mere utilitaiianism is driven to the strangest devices in 

 its attempts to do the same thing. 



Mr. Boulger speaks of the development of corolla at tlie 

 exjense of stamens as a " degradation of organs," and regards it 

 in the light of a disease. Many botaniits would agree with him, 

 no doubt. But where is the proof of this ? Is a plant produced 

 for the mere purpose of ;v-production ? Is that even its highest 

 purpose? Whatever b;aiUy maybe, the reproductive process is 

 assuredly a mean;, and not an end. 



There is some ground for the hypothesis that the flower of a 

 plant represents its nervous centre, that it is the analogue, per- 

 haps even the homologue, of the brain and countenance of the 

 higher animals. In vegetables the reproductive organs are 

 associated with this nervous centre. But they are not so pl.aced 

 in animals, and if they had been otherwise arranged in vege- 

 tables the blossom might siili have been the crowning beauty of 

 the plant. 



I do not admit that the metamorphosis of stamens into corolla 

 is a degr.adatioii at all. I am no", sure whether the production of 

 perfectly double and perfectly barren flowers ought not to be 

 reg.arded as the final goal of every species of plant — the point at 

 which reproduction becomes no longer necessary, because the 

 life-wave of that species has reached its climax and needs no 

 further to be carried forward from generation to generation. 



Finally, the point at issue amounts to this : Is colour in 

 flowers a mere expedient for getting them cross-fertilised ? or is it 

 a natural and necessary phase in the dtvelopment of plant-life, 

 which serves also the secondary purpose of securing the advan- 

 tage of cross-feitilisation ; as the brain of man, which is primarily 

 the great organ of thought and sentiment, serves also the secon- 

 dary purpose of selecting wholesome food ? 



I hold to the latter view, which includes and accounts for all 

 that the other does, and much besides. F. T. MoTT 



Leicester 



Lord Rayi.eigh, in Nature, vol. xl. p. 6, questions 

 whether the colour- sensations of insects are analogous to ours. 

 As tending to illustrate this subject, let me quote the following 

 paragraph from the scientific column of i\xe Iltiistiated News oi 

 April 2, 1870, p. 362 : — 



"The spectrum of the light of the firefly has been examined, 

 and it is found to be perfectly continuous, without traces of lines 

 either bright or dark. It extends from about the Une C in the 

 scarlet to F in the blue, and is composed of rays which act 

 powerfully on the eye, but produce little thermal or actinic effect. 

 In other words, the fly, in producing its light, wastes but little of 

 its power." 



This, it is true, tells nothing as to the colour-sensations of the 

 insect, but it appears to show that the same rays are luminous to 

 its eyes which are luminous to ours. 



Joseph John Murphy 



Old Forge, Danmurry, Co, Antrim, Nov. S 



