April i,, 1872] 



NATURE 



449 



February, it will be seen, was entirely free from frost, the 

 minimum for that month being 32° '4, on the 28th. The 

 warmest period was from March I to 8, when the maximum tem- 

 perature ranged each day from 57*-i to 6o°-S. It will be interest- 

 ing to know whether so long a period of exceptionally high 

 temperature, including fifty-three consecutive days entirely free 

 from frost, has ever been recorded before in the depth of 

 winter. On March 19 the average temperature of the day fell 

 below the mean, and continued so for nine days, till the 27th. 

 The minimum temperature for March was on the 21st, zb'-z 

 Fahr., being the lowest recorded since Dec. 9. There were nine 

 frosty nights in March, against the two in the whole of the two 

 preceding months. For the week ending March 26 the mean 

 temperature was 34°, or 16° lower than the mean for the week 

 ending March 7. 



A CORRESPONDENT of The Blue strongly urges the desirability 

 of the formation of a Natural History Society at Christ's Hos- 

 pital ; and the editor of that magazine promises his assistance to 

 the proposal. We heartily wish it success. 



The proposed Act for appropriating the Yellowstone Park for 

 public purposes (to which we recently referred), has passed the 

 Congress of the United States. The following are extracts from 

 the Bill :— " That the tract of land in the territories of Montana 

 and Wyoming (as already described) is hereby reserved and 

 withdrawn from settlement, occupancy, or sale under the laws of 

 the United States, and dedicated and set apart as a public park 

 or pleasuring-ground for the benefit and enjoyment of the people. 

 That said public park shall be under the exclusive control of 

 the Secretary of the Interior, whose duty it shall be, as soon as 

 practicable, to make and publish such rules and regulations as 

 he may deem necessary or proper for the care and management 

 of the same. Such regulations shall provide for the preserva- 

 tion from injury or spoliation of all timber, mineral deposits, 

 natural curiosities, or wonders within said park, and their reten- 

 tion in their natural condition. The Secretary may, in his dis- 

 cretion, grant leases for buil.iing purposes for terms not exceeding 

 ten years, of sma 1 parcels of ground, at such places in said park 

 as shall require the erection of buildmgs for the accommodation 

 of visitors ; all of the proceeds of said leases, and all other re- 

 venues that may be derived from any source connected with said 

 park, to be expended under his direction in the management of 

 the same, and the con»tiuction uf roads and brille paths therein. 

 He shall provide against the wanton destruction of the fish and 

 game found within said park, and against their capture or de- 

 struction for the purposes of merchandise or profit." Such a 

 step in the interest of science deserves more than a passing 

 recognition from this side the water. 



The British Medical Journal prints the following admirable 

 reply to the extraordinary article which appeared in the Saturday 

 Rez-iezv of the i6th ult., on Dr. LieLreich's lecture on "Turner 

 and Mulready," which we gave last week: — "It is not, of 

 course, always to be expected that Saturday Reviewers should 

 have a very profound knowledge of their subjects ; but it might 

 be thouglit advisable that an analysis of an optical argument 

 should not be publicly undertaken by a gentleman who is igno- 

 rant uf the first rudiments of the subject, and .-o httle acquainted 

 with even the alpha et of its language as the gentleman who 

 discusses, in the last Saturday Review, the visual defects of 

 Turner and Mulready. He pronounces a 'verdict of not 

 proven ' on Mr. Liebreich's argument ; and his -fitness for ap- 

 preciating a discussion of the effects of yellow discoloration of 

 the lens, occui-ring with advancing old age, on Mulready's per- 

 ception of colour, may be estimated by the following sentence : 

 ' Let us suppose a person to put on a pair of yellow spectacles. 

 The effect is assumed to be, and we think correctly, that the 

 yeVoiv in a landscape or in a picture, unless extra strong, would 



be scarcely recognised ; and that the blues also, unless very 

 decisive, would be neutralised. The consequence seems to 

 follow, that the painter would throw ultra force into both yellow 

 and blue: though against this supposition it must not be for- 

 gotten that the spectacle or the crys:alline lens, as the case may 

 be, would discolour precisely in the same degree the tones in 

 nature and the figments on the palette.' The italics are ours. 

 There is scarcely a word in this astonishing statement which is 

 not entirely a mistake. It was not assumed, but it is known, 

 that, seen through a yellow glass, the yellows in a landscape are 

 seen relatively more strongly, while the blues are partly neutra- 

 lised. It was not assumed that the effects of viewing a landscape 

 and a picture through a yellow lens or glass are the same ; but, 

 on the contrary, it was stated, as the result of experiment, that 

 they are entirely different. The retina becomes presently so far 

 accustomed to the yellow medium, that the strong lights reflected 

 from blue surfaces in nature overpower the yellowness of the 

 medium, and the blues of a landscape are presently but little 

 neutralised. The reflections from pigments, poor imitations as 

 as they are, at the best, of nature, have not the same power ; a 

 large part is neutralised by the yellow glass or lens ; and to 

 produce with pigments, on a canvas, blues which satisfy his eye 

 as comparable with those which he sees in nature, the painter^ 

 who in old age has the pigment-yellowness of senile change in 

 the lens — employs much deeper blues than he would have done 

 in youth, or than impress youthful eyes as representing the 

 natuial tints ttuthfuUy. That is why, on Liebreich's theory, 

 Mulready, in painting the same picture in old aije which he had 

 painted in middle life, introduced ultramarine into the flesh tints 

 — painted a linen smock of the brilliancy of a glittering silk ; 

 and that is the key which he affords to the prevailing excess of 

 purple tints which the official catalogue describes as characteri- 

 sing the latest works of this great artist. The great master him- 

 self was, in his later life, dissatisfied for this reason with the 

 colour of his earlier works ; he thought them too brown, and 

 used to warn his pupils to paint with stronger blues, especially 

 in the grey shadows.' 



In a letter addressed by von Heuglin to Middcndorff, of the 

 St. Petersburg Academy, we find the fullest details of the explo- 

 rations instituted by that eminent traveller during the past 

 summer in the Nova Zembla seas. In this he remarks that the 

 original plan included a visit to the mouths of the Obi and 

 Yenisei, perhaps even extending to the island of New Siberia. 

 This, however, was found to be impracticable on account of un- 

 seasonable weather, as it was not till the 6th of August that 

 they reached the Straits of Matotschkin. Up to that time they 

 had met with no ice ; but after passing the straits to the east 

 there was very much drifc ice from the sea of Kara so as almost 

 to bar their way. Finding that the northern coast of the island 

 was entirely embargoed by ice, they turned to the south, and in 

 passing visited the Straits of Kostin and the Nechwatowa, thtn 

 Waigatsch, and finally arrived at the Straits of Jugorsky on the 

 1st of September. Here the expedition did not make any better 

 progress than in the Straits of Matotschkin, and fearing that 

 they might be shut in by the ice for the winter, they returned to 

 their starting-place. Among the more important results of the 

 voyage were numerous soundings and mersurements of deep-sea 

 temperatures, as also various geographical determinations ; while 

 large collections of specimens of natural history were brought 

 together. Among these the most interesting was the discovery 

 of two different species of lemming in Nova Zembla, and it wss 

 thought possible that in Southern Nova Zembla still a third 

 species might be met with. The same animal was also found in 

 Spitzbergen. Numerous birds were obtained in Nova Zembla 

 and Waigatsch ; among them the Mandt's Guillemot. Of fishes, 

 some species of cod, cottus, and salmon were obtained, and about 

 one hundred species of plants. 



