May 27, 1875] 



NA TURE 



67 



second two miles of the road were quite straight ; so that I could 

 easily have seen the dog if he had been merely running a com- 

 paratively short distance in front of the liorsea. Why this animal 

 should never have returned to his former home on his own 

 account, I cannot sugsjest ; but I think it was merely due to an 

 excessive caution which he also manifested in other things. Be 

 the explanation of this, however, what it may, as a fact he never 

 did venture to come back upon his own account, notwithstanding 

 there never was a subsequent occasion upon which any of his 

 former friends went to the town but the terrier was sure to 

 return with them, having always found some way of escape from 

 his intended imprisonment. 



Regent's Park, N.W. George J. Romanes 



Equilibrium of Gases 



In a former letter (Nature, vol. xi. p. 486) I ventured to 

 express an opinion contrary to that of most authorities, that the 

 temperature of a vertical column of gas at rest would tend to 

 diminish from below upwards. 



I then stated that there was nothing to counteract the ten- 

 dency to the upward diminution of energy which must result 

 from gravitation. I am indebted to Mr. S. H. Burbury for pointing 

 out to me that a counter-action exists in the removal from the 

 system, at every point of the ascen^, of those molecules whose 

 vertical energy at that point is nil. The total mean energy of 

 the molecules may thus remain the same, although a constant 

 deduction is made from the energy of every molecule remaining 

 in the system. 



Mr. Murphy's argument (Nature, vol. xii. p. 26) from the 

 absence of cumulus in the Arctic regions, is also a sound one as 

 far as it goes, and fairly counterbalances that derived from tro- 

 pical calms and storms. 



I must therefore withdraw my dissent from the generally 

 received doctrine of the tendency to equality of temperature in a 

 vertical column. R. C, Nichols 



Athenaium Club, May 20 



Contributions to the Natural History of the Wolf (C^zw/V 

 pallipes) of Northern India 



Having had the opportunity of examining a number of wolf- 

 cubs, it may not be without some interest to record my observa- 

 tions in your useful journal. 



This year (1874-75) I examined fourteen batches or litters of 

 wolf-cubs between December 18 and February i. Judging from 

 the apparent ages of the different litters, I should fix the breed- 

 ing time of the wolf from about the middle of October to about 

 the end of December. But the majority are bred in December, 

 as out of the fourteen batches I could approximately fix the birth 

 of eleven of them in some date of December. On the 29th of 

 December a full-grown she-wolf, in milk, was brought to me, 

 with seven cubs, which appeared to be about a week old. She 

 had ten teats. The eyes and ears of the cubs were closed ; their 

 ears were drooping ; their general superficial colour was sooty 

 brown, with an under colour, that is, at the roots of the hairs, of 

 dirty light tan. The latter colour was more marked on the 

 head and flanks, while the sootiness was more decided on the 

 hinder part of the body. They all had a milk-white chest-spot 

 varying in size. Six of them had white hairs at the tips of their 

 tails. 



All those I "examined, of about this same age, had similar 

 characters. When the eyes of young wolves open, and they 

 begin to crawl, about the third week, their general colour is a 

 dirty light tan, washed with soot. As they grow, their ears 

 become erect, their general colour a uniform light tan, with only 

 the tips of the hairs dark, the tail being the darkest part of the 

 animal. After the sixth week or so, the white chest-spot 

 emerges into the light fawn colour of the remainder of the chest, 

 and a dark collar on the under part of the neck becomes visible. 

 This collar looks as if dark grey ashes were brushed across the 

 greyish white of the neck. All those I examined which looked 

 older than four or five weeks had this collar. But it disappears 

 again as the wolf gains its adult colouring, becoming merged 

 into the uniform creamy white of the neck and chest. Out of 

 seventy-nine wolf-cubs which I examined, all but one had a 

 white chest-spot, varying in size from a few hairs to a patch the 

 size of a rupee. Fourteen of them had white tips to their tails, 

 varying in size. Seventeen of them had white tips to one or more 

 of their feet. These white marks leave no doubt about the close 

 relationship between the wolf and the domestic dog. The sex 



of seventy-four cubs was note 3, belonging to thirteen litters. 



Forty were males, and thirty- foar were females. The number ot 

 young at a birth was from three to eight. 



Lucknow E. Bonavia 



OUR ASTRONOMICAL COLUMN 

 I Leporis (Fl.).— This star is wantinjj in both Arge- 

 lander's Uranometria and in Heis's Atlas, though the 

 estimations of magnitude are very accordant ; indeed, 

 with the exception of Lalande, who calls it 6J observers 

 including Flamsteed, Bradley, Piazzi, and Johnson 

 appear to have uniformly estimated it . It x'i \s' s.p. 

 e Leporis, a star of the 4th magnitude. Baily has this 

 note : " The star is designated as of the 9th magnitude in 

 the British Catalogue j bat I apprehend this is a typo- 

 graphical error, as it is stated to be the 6th in the original 

 entry." Yet, the star having been omitted by Argelander, 

 and particularly by Heis, there remains a suspicion of 

 variability of light. 



The Comet of December 1872 (IClixkerfues— 

 Pogson). The observation of a telescopic comet by 

 Mr. Pogson, at Madras, on the mornings of December 3 

 and 4, 1872, in consequence of a telegraphic message 

 from Prof. Klinkerfucs, of Gottingen, that Biela's Comet 

 had "touched the earth" on November 27, and might 

 be sought for near the star 6 Centauri, will be fresh 

 in the recollection of our astronomical readers. The 

 remarkable shower of meteors on that evening had 

 exhibited a radiant almost identical in position, with 

 the diverging point, which meteors moving in the orbit 

 of Biela's Comet would have, and hence the assump- 

 tion of our close proximity to this body during the 

 meteoric display. Places of the comet detected by Mr. 

 Pogson in the first interval of favourable weather after 

 receiving the telegram were communicated by him in the 

 same month to the Astronomer Royal and Prof. Klinker- 

 fues, but without details of the observations upon which 

 they were founded. With the aid of these positions the 

 question of identity of Pogson's Comet with one of the 

 bodies forming Biela's Comet was examined. There was 

 at the outset this difficulty in the way of entertaining the 

 idea of identity, that if Biela's Comet were actually close 

 to the earth on the evening of November 27, its perihelion 

 passage would have taken place on the 27th of the fol- 

 lowing month, ten or eleven weeks later than the date 

 indicated by Michez's orbit as perturbed to 1866 ; never- 

 theless, since the comet was not detected in i86;-66, in 

 the track it should have followed according to Michez's 

 calculations, though the largest telescopes were em- 

 ployed in a search for it, there remained the possi- 

 bility of disturbance of the mean motion in 1852, when 

 observations were last obtained, from some unknown 

 cause. Klinkerfues, therefore, assuming the elements 

 of Biela's Comet, examined their relation to Pogson's 

 places, and arrived at the conclusion that the identity of 

 the comet observed at Madras with one of the two Biela 

 comets could hardly be doubted. Subsequently, Prof. 

 Oppolzer, of Vienna, gave attention to the subject : he 

 remarked that with Michez's orbit of Biela, Pogson's 

 observations were not represented upon any supposition 

 as to date of perihelion passage, but with the semi-axis 

 of Biela, and assumed small distances of the comet from 

 the earth at the time of the Madras observations, he 

 deduced several sets of the other elements bearing 

 greater or less similarity to those of Biela, and indicating 

 a very near approach to the earth on November 27th : 

 his conclusion was, that Pogson's Comet stands with high 

 probability in intimate connection with the meteor- 

 shower of that evening ; and it is at least possible that 

 the observed object was really one of the heads of Biela. 

 Since these investigations, the full details of the 

 Madras observations have been published in the Astro- 

 no7nische Nachrichten, and Prof. Bruhns, of Leipsic, has 



