424 



NATURE 



S^March 28, 1878 



orbit might (for anything we can say to the contrary) have been 

 beyond the present orbit of Jupiter. However slowly we may 

 suppose the earth to be approaching the sun, yet in the vast 

 epoch of time (which is precisely what is necessary in order to 

 harmonise with geological evidence) it may have approached 

 millions of miles towards the sun. There is one point of pecu- 

 liar harmony here which is worth noticing in connection with 

 this, viz., as the sun cools down or gives out less heat to the planets, 

 so the planets reduce their distance from the sun ; thus tending 

 to equalise the heat conditions suitable for life. Thus, although 

 the heat of the sun when first formed may have been enormously 

 greater than it is at present, yet on account of the distance of 

 the planets (including the earth) from it at that remote time, the 

 conditions for life may have been as favourable as now, and thus 

 the first geological changes may have commenced on the earth 

 at that remote epoch when the sun was an incandescent nebula 

 occupying a vastly greater volume than now (perhaps even the 

 volume of the earth's present orbit), or' under these conditions 

 any interval of time for life on the earth that geological evidence 

 may require is afforded. 



4. There is another point that would appear to be of interest 

 in connection with this subject. The rate at which a planet 

 approaches the sun through friction in the media in space would 

 depend (admittedly) on its mass, or would be greater when its 

 mass is less. It follows evidently from this therefore that the 

 great planets, Jupiter, Saturn, &c., must have approached the 

 sun at a slower rate than the earth (or the smaller planets gene- 

 rally). It would follow therefore (more particularly in view of 

 the vast epoch of time demanded by geology) that the relative 

 position of the planets must have changed from this cause, that 

 the earth, for example, must at one time have been nearer Jupiter 

 than at present ; more especially as the greater velocity of the 

 earth in its present contracted orbit causes greater friction (and 

 thereby brings the earth more rapidly towards the sun). Indeed 

 it is an evident consequence of this principle that it would require 

 only a certain relative difference in mass of the planets (or in the 

 length of the elapsed tinie) to have made the small planets occupy 

 positions beyond the larger planets originally, and so the positions 

 of the planets to have been reversed, i.e., the smaller planets 

 furthest from the sun, and the larger planets nearest. The 

 tendency of the friction evidently is to arrange the positions of 

 the planets, so that the larger are furthest from the sun.^ This 

 it may be noted is the position at the present time. We do not 

 of course mean to assume necessarily that there has been an 

 actual reversal in the positions of the planets ; all we adduce is 

 that friction must inevitably tend to change relative position, 

 when the masses of the bodies are different, and whether the 

 positions are reversed depends therefore on the time during 

 which this cause was in operation (and here we are considering 

 especially the vast interval of time required by geology) — the 

 change of relative position being more rapid the greater the 

 relative differences of the masses. Thus it is a known fact that 

 a meteorite approaches the su^ or contracts its orbit at an enor- 

 mously more rapid rate than a planet. It is so far certain that 

 through friction in the medium known to exist in space, the 

 planets (whose masses are different) must have changed to some 

 degree their relative positions, or that the earth (for example) 

 must have been nearer Jupiter at one time than it is now. These 

 it should be observed cannot be regarded as speculations, but 

 rather as deductions dependent on accepted principles. 



5. Time may evidently have as great significance in physical 

 as in geological changes, or in giving time its full import great 

 results may follow ; and it will be admitted that it is of interest 

 to trace the slow operation of causes into their legitimate results 

 through lengthened time epochs, not confining the attention to 

 the infinitesimally narrow range of human experience. 



London, March 21 S. Tolver Preston 



English Lake-dwellings and Pile-structures 



General Lane Fox has described the old, and, in some 

 cases, successive pile-works in the peat of Finsbury and South- 

 wark, outside Roman London {Anthropological Review, vol. iv. 

 No. 17, April, 1867, pp. Ixxi. et seq.). Another very interesting 

 case was evidently under Sir C. Bunbury's observation in 1856, 



' It would seem a rather curious fact to note that those planets which 

 contain within themselves the g^reatest store of heat (ie., the large planets), 

 ind which theref jre would probably be the longest time before they were 

 adapted to the conditions of life, are those which approach the sun the 

 Blowest. It is also evident that the fact of the earth being a small planet, 

 .would tend to augment the difference between the range of its present, and 

 that of its original, orbit. 



near Wretham Hall, six miles north of Thetford, where, in a 

 drained mere, "numerous posts of oak-wood, shaped and 

 pointed by human art, were found standing erect, entirely buried 

 in the peat." Red-deer antlers, both shed and broken from the 

 skull, and also saivn off, were found in this peat. (See Quart, 

 yourn. Geol. Soc, vol. xii., p. 356.) 



Since writing the above, I have been informed that Mr. W. 

 M. Wy lie, F.S. A., referred to this fact in " Archseologia," vol. 

 xxxviii., in a note to his excellent memoir on lake-dwellings. I 

 can add, however, that regains of Cervus elaphus (red deer), 

 C. dama ? (fallow deer), Ovis (sheep). Bos longtfrons (small ox), 

 Sus scrofa (hog), and Canis (dog), were found here, according 

 to information given me by the late C. B. Rose, F.G. S., of 

 Swaffham ; who also stated, in a letter dated August 11, 1856, 

 that in adjoining meres or sites of ancient meres, as at Saham, 

 Towey, Carbrook, Old Buckenham, and Hargham, cervine 

 remains have been met with : thus at Saham and Towey, Cervus 

 elaphus (red deer) ; at Buckenham, Bos (ox) and Cervus capreolus 

 (roebuck) ; at Hargham, Cervus tarandus (reindeer). 



The occurrence of flint implements and flakes in great numbers 

 in the site of a drained lake between Sandhurst and Friraley, 

 described by Capt. C. Cooper King, in the Journal of the Anthro- 

 pological Institute, January, 1873, p. 365, &c., points also in all 

 probability to some kind of lake-dwelling, though timbers were 

 not discovered. 



Lastly, the late Dr. S. Palmer, F.S. A., of Newbury, reported 

 to the "Wiltshire Archoeolo^ical Society" in 1869, that oaken 

 piles and planks had been dug out of boggy ground on Cold Ash 

 Common, near Faircross Pond, not far from Hermitage, Berks. 



T. Rupert Jones 



Selective Discrimination of Insects 



As bearing on the question discussed by " S. B.," and by Mr. 

 Bridgman and others, at p. 163 ante, and in previous numbers 

 of Nature, the following observations may have some interest. 

 One day in the latter part of July, 1877, I took on a flower of 

 red clover ( T. pratense) an humble-bee {Bombus Carolina ?), 

 having the hairs of its body and legs densely dusted with pollen- 

 grains of an Althcea, which was in full blossom in the same 

 enclosure, about one hundred feet from the spot where I took 

 the bee. 



On the same day and at the same place I attempted to take 

 another Bombus, which was ravishing a flower of the same spe- 

 cies of clover. It escaped me, and, flying to a distance of about 

 twenty feet, alighted on a flower of a Canada thistle {Cirsitnn 

 arvense), into which it immediately plunged its tongue. After 

 watching it feed for a moment or two, I again attempted to cap- 

 ture it, when it again escaped, and, flying to about the same dis- 

 tance as before, alighted on a flower of a larkspur {Delphinium 

 Consolida), and upon my third attempt to take it, it flew away 

 and disappeared. 



As to whether insects are attracted by odour or colour, I wish 

 to call attention to an observation of Mr. Crouch, as detailed by 

 Mr. Gosse in "A Year at the Shore." " Tealia crassicornis is 

 as good a mimicry of the great dahlias as the Sagartics are of the 

 daisies." " Even bees are occasionally deceived. Mr. Crouch, 

 when once looking at a fine specimen which was expanded so 

 close to the surface that only a thin film of water covered the 

 disc and tentacles, saw a roving bee alight on the tempting sur- 

 face, evidently mistaking the anemone for a veritable blossom." 



Covington, Ky., U.S.A. V. T. C. 



The Telephone as a Means of Measuring the Speed 

 of High Breaks 



In some experiments with an induction coil and wheel break 

 which I have lately been engaged on I have found the telephone 

 useful in determining the number of times per second in which the 

 current is broken. 



For this purpose it may be attached to the secondary terminals, 

 or the whole or part of the primary current may be passed 

 through it. 



The telephone may also be used generally for determining the 

 speed of elecro-magnetic motors by taking advantage of the 

 fact that the current driving them is either short-circuited or 

 broken a definite number of times in each revolution. The tele- 

 phone wires may in this case be attached at two points some 

 distance apart on one of the battery wires. The note of the 

 telephone gives the number of breaks per second. 



Pixholme, Dorking, March 17 J. E. H. Gordon 



