504 



NATURE 



\yan. 30, 1890 



marking seven stages of growth, the variation in form — from 

 youth to the adult stage — embraces characteristics covering 

 " most of the distinctions upon which many of the Austrahan 

 forms mainly depend for the recognition of distinct specific 

 rank." Such being the variability of local form in the indi- 

 viduals of the various stages of growth, Mr. Johnston thinks 

 there is good reason for the belief that the several forms erected 

 into specific ranks in various parts of Australia may prove to be 

 local varieties, or particular stages of growth of one widely 

 distributed species. 



The destruction of the native opossum is attracting some 

 attention in Tasmania. It is said that about 75 per cent, of the 

 animals killed have had young in the pouch at the time. The 

 opossum has great commercial value, and there seems to be a 

 general opinion that it ought to be efficiently protected. 



In the third report of the Liverpool Marine Biological Station 

 on Puffin Island, Prof W. A. Herdman gives a concise and 

 interesting account of much good work done during the past 

 year. In the autumn the station was closed, but it will be re- 

 opened at the beginning of either April or May, and Prof. 

 Herdman has no doubt that next summer all the different lines 

 of investigation hitherto started will be followed up with a 

 renewed enthusiasm which will more than make up for the loss 

 of the winter observations. 



The Annuaire de VAcadentie Royale de Belgiquc for the current 

 year contains the usual information about the Academy and the 

 awards of the various prizes. There is little to interest non- 

 members except the series of biographies and portraits of former 

 distinguished members, including Houzeau. 



Dk. C. Hart Merriam, chief of division of ornithology and 

 mammalogy, in the U.S. Department of Agriculture, has issued a 

 series of directions for the measurement of small mammals and 

 the preparation of museum skins. The directions are accompanied 

 by an illustration, showing the appearance of a well made skin. 



Mr. de Zilva Wickremasinghe, assistant librarian of the 

 Colombo Museum, has compiled a valuable list of the " Pansi- 

 yapanas Jataka," the 550 birth stories of Gautama Buddha. In 

 order to make the record complete the compiler consulted many 

 old manuscripts belonging to temple libraries in various parts of 

 Ceylon. The list has been published in the Journal of the Ceylon 

 branch of the Royal Asiatic Society, and is also printed separately. 



Solutions to the questions in Pure Mathematics, Stages I. 

 and II., set at the May examinations of the Science and Art 

 Department from 1881 to 1886, have been published by Messrs. 

 Chapman and Hall in book form. Each of the questions has 

 been fully worked out, and together they make a useful series of 

 examples in elementary mathematics. 



Messrs. Dulau and Co. have issued a catalogue of works 

 relating to cryptogamic botany. 



We have to acknowledge receipt of £2, sent by Mrs. Morton 

 Sumner towards the payment of the debt on the laboratories of 

 Bedford College, to which we called attention last week. 



An interesting paper is contributed by Prof. Carnelley to the 

 Philosophical Magazine for January, in which he attempts to 

 express the periodic law of the chemical elements by means of 

 an algebraic formula. For reasons which are given in detail 

 in the memoir, an expression of the form A = c{m 4- ^Iv) is 

 adopted, where A represents the atomic weight of the element, 

 c a constant, m a member of a series in arithmetical progression, 

 depending upon the horizontal series in the periodic table to 

 which the element belongs, and v the maximum valency or the 

 number of the vertical group of which the element is a member. 

 From a number of approximations. Prof. Carnelley finds that m 



is best represented by the value o in the lithium-beryllium-boron 

 &c., horizontal row, by 2h in the sodium series, 5 in the potas- 

 sium series, and 8i, 12, 154, 19, 22i, &c , in the subsequent 

 rows. Thus m is a member of an arithmetical series of which 

 the common difference is 25 for the first three members, and 3J 

 for all the rest. On calculating the values of the constant c from 

 A 



the equation c 



for 55 of the elements, the numbers 



m -I- sl'v 



are all found to lie between 6'0 and 7*2 with a mean value of6'6 

 In by far the majority of cases the value is much closer to the mean 

 6 '6 than is represented by the two extreme limits, thus in 35 

 cases the values lie between 6*45 and 6'75. If the number 

 6 "6, therefore, is adopted as the value of c, and the atomic 

 weights of the elements are then calculated from the formula 

 A = 6 6{m -\- is/v), the calculated atomic weights thus obtained 

 approximate much more closely to the experimental atomic 

 weights than do the numbers derived from an application of the 

 atomic heat approximation of Dulong and Petit. The number 

 6 6 at once strikes one as being remarkably near to the cele- 

 brated 6'4 of Dulong and Petit, and Prof. Carnelley draws the 

 conclusion that there must be a connection between the two. 

 This assumption appears to be supported by the following inter- 

 esting facts. If we assume c to represent the atomic heat, then 

 atomic weight = atomic heat x {m -f- ,^/v) = atomic weight x 



specific heat x (m + Jv) : or specific heat = ^ . O" 



calculating the specificheats of the elements from this equation, they 

 are found to agree remarkably well with the experimental values, 

 except in those cases in which the observed specific heat is known to 

 be abnormal. Again, Bettone has shown that the hardness of the 

 elements is inversely proportional to their specific volumes. If 

 this be so, hardness = ^^- ' gravi y _ ^^^^ ^^ calculating the 



hardness from this formula, the numbers are again found to 

 agree very closely with the hardness experimentally determined 

 by Bettone. That the periodic law may therefore be approxi- 

 mately expressed by a formula of the type A = c{m + ^/v) 

 appears very probable, and that the number 6 '6 is a very close 

 approximation to the value of c appears also to be established. 

 Moreover, the fact that m in the even series represents a whole 

 number, while in the odd series it represents a whole number and 

 a half, corresponds to ihe well-known difference in chemical pro- 

 perties between the members of these series ; and the assumption 

 that the common difference between the first three values of ;;/ is 

 only 22, while between all the rest it is 35, is borne out by 

 Mendeleeff's statement that the elements of the lithium and 

 sodium rows are more or less exceptional in their nature, and 

 not strictly comparable with the subsequent series. 



The additions to the Zoological Society's Gardens during the 

 past week include two Brown Capuchins i^Cebus falttellus i 6) 

 from Paraguay, presented by Mr. E. Malateste ; a Bonnet 

 Monkey {Macacus siidcus $ ) from India, presented by Miss 

 Alice Booth ; a Macaque Monkey (Macaais cynomolgiis i ) from 

 India, presented by Mr. C. Harris ; a Green Monkey 

 {Cercopithecus callitrichus tj ) from West Africa, presented by 

 Quarter- Master Serjeant Mathison, W.I.R. ; a Silver Pheasant 

 {Euplocamus nycthtmerus 6 ) from China, presented by Mr. W. 

 R Rootes ; a Malbrouck Monkey [Cercopithecus cynosurus i) 

 from Rorke's Drift, South Africa, a Bonnet Monkey [Macacus 

 sinicus ? ) from India, deposited. 



OUR ASTRONOMICAL COLUMN. 



Objects for the Spectroscope. 



Sidereal Time at Greenwich at 10 p.m. on January 30 = 6h. 

 40m. 20s. 



