September 25, 1890] 



NATURE 



52, 



classes and superintended the teaching in the labora- 

 tories, Dr. Carnelley did not forget that the first duty of 

 a man of science is to advance his subject. That he did 

 so with good effect is seen from the numerous communi- 

 cations of importance contributed to the various learned 

 societies both in this country and in Germany, either 

 alone or in conjunction with other investigators. Pro- 

 minent amongst the researches with the results of which 

 he has enriched science are those by which he sought to 

 extend the application of Mendeleeff's discovery of the 

 " periodic law," in accordance with which the chemical 

 and physical properties of the elements and of their com- 

 pounds are periodic functions of the atomic weights of 

 the elements. Carnelley, when a student at the Owens 

 College, appears to have been greatly impressed with 

 Mendeleeff's conceptions, and it was to the study of the 

 physical properties of the elements and their compounds, 

 and to the devising of new methods of obtaining trust- 

 worthy determinations of the melting-points of metallic 

 salts and the elements, that he early devoted his energies. 

 The results of these experiments were subsequently 

 utilized to show that the fusibility of the elements and of 

 certain of their compounds is a periodic function of their 

 atomic weights. From the relationships discovered by 

 him to exist between the melting-points of the chlorides 

 of the elements and the atomic weights of those elements 

 Carnelley was led to draw conclusions respecting the 

 atomic weight of the element beryllium and to fix its posi- 

 tion in the classification of the elements. 



Other physical properties have been shown by Car- 

 nelley to be related to the atomic weights of the elements, 

 and in a paper read at the Aberdeen meeting of the 

 British Association he developed a series of analogies 

 between the elements and various series of hydrocarbons, 

 from which he concluded that the chemical elements may 

 be represented by a formula A„B2n+(2-:r), in which n is the 

 series and x the group to which the element belongs ; 

 A = 12 and B = - 2. In a paper published in the Philo- 

 sophical Magazine in January last, he tells us that since 

 1872 he had attempted to give the periodic law a simple 

 numerical expression, and states that early in the summer 

 of ,1889 he had obtained such an expression, in which the 

 atomic weight is represented as equivalent to the product 

 of a constant, c, into a factor made up of in, a member of 

 an arithmetical progression, dependent on the series to 

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

 or the number of the group of which the element is a 

 member. Thus— 



A = c\in-\- v^'X 



The best results are obtained when jr = 2, and in is o for 

 series II., 2* for III., 5 for IV., 8^ for V., 12 for VI., 15^ 

 for VII., 19 for IX., 22^ for X., 26 for XL, and 29^ for 

 XII. 



The formula thus becomes A = c{in -f sjv), and m is a 

 member of an arithmetical series in which the difference 

 is 3i, save in the first two series, when it is i\,. By using 

 this equation, the value for c in the case of 55 elements 

 is found to lie between 6-o and 72, with a mean value of 

 6-64. Accepting 6-6 as the value of c, the calculated 

 atomic weight of sodium, for example, would be found as 

 follows : — Sodium is the first member of series III., in is 

 therefore 2-5 and ^' = i, so that A = 6-6(2-5 -f sj\)\=- 23-1. 

 In the paper referred to the atomic weights of all the ele- 

 ments are given as calculated by this formula, and compared 

 with those generally accepted. The results obtained exhibit 

 very near approximation, the calculated values being, in 

 fact, nearer the experimental numbers than those obtained 

 by the aid of Dulong and Petit's law. The remarkable co- 

 incidence that the value 6-6 for the constant c in the 

 above formula very nearly approximates to the value 64, 

 accepted as the atomic heat of the elements, in acccord- 

 ance with Dulong and Petit's law, is noted, and that the 



NO. 109 1, VOL. 42] 



specific heats of the elements may consequently be repre- 



sented as equivalent to 



The specific heats cal- 



culated by the aid of this formula are compared with the 

 experimental values, and in the case of the 55 elements, 

 in which a comparison can be instituted in 45 instances 

 the agreement is very satisfactory, while the other 10 are 

 elements the specific heats of which, according to Dulong 

 and Petit's law, are more or less abnormal. 



Accepting Bettone's conclusion that the hardness of an 

 element is inversely proportional to its specific volume, it 

 is shown that hardness mav be represented in terms of 

 the specific gravity, and the expression 6"6(w + sjv)^ 

 thus— 



Hardness = L^ = ^P-i^ = . #'1 V V 



spec. vol. at. wt. 6-6(w + >Jv) 



But Carnelley's energies were not alone given to the in- 

 vestigation of questions of a purely scientific interest, for, 

 naturally, one situated as he was all his life in the midst 

 of active industrial communities found many opportuni- 

 ties of applying his knowledge and training for the benefit 

 of those around him. Notably was this the case in the 

 valuable examinations, chemical and bacteriological, of 

 the air of dwellings, schools, tSic, in Dundee and district, 

 in a report to the School Board, of which he was an 

 active member. Much valuable information was brought 

 to light by these investigations, and it would appear that 

 one result attained was the realization by the authorities 

 in Dundee, Aberdeen, and some other towns, of the 

 necessity of making provision in schools for the supply of 

 a pure aerial food for the scholars. This subject — the 

 ventilation and heating of schools, &c. — was, we believe, 

 one with which he was busily engaged at the time of his 

 last illness, and it is to be hoped that the labour which 

 he expended upon it will [be continued by one of his 

 competent collaborateurs. 



Prof. Carnelley was also the author of an elaborate and 

 most valuable compilation of certain physical constants 

 of chemical compounds, published in two large volumes, 

 a monument of industry and devotion to science ; he was, 

 moreover, an extensive contributor to the German- 

 English dictionary of scientific and technical terms 

 published by Messrs. Vieweg and Son, of Brunswick. 



Of a retiring, modest, unselfish, and deeply religious 

 nature, his earnest enthusiasm served not only to create 

 in all a sincere regard for him, but to make him beloved 

 by those who were privileged, whether as teachers or 

 students, to become intimately acquainted with him. At 

 all times an ardent student, an untiring investigator, a 

 successful teacher, and a contributor in so great a variety 

 of ways to the advancement of science, by his early death 

 an already brilliant career has been deplorably cut short 

 and a vacancy created in the ranks of scientific men in 

 this country which must long remain unfilled. 



H. E. R. 



P. P. B. 



NOTES. 

 The well-known writer on vegetable palreontology, Prof. E. 

 Weiss, of Berlin, died on July 5 last. 



The Swedish residents of Chicago have subscribed for a 

 statue of LinniEus, which will shortly be erected in the Lincoln 

 Park in that city. 



Dr. a. Moller, of Berlin, has established, at Blumenau in the 

 State of S. Catharina in South Brazil, with the assistance of the 

 Prussian Academy of Sciences, a botanical laboratory, where, 

 during the next two years, he will pursue Brefeld's method 

 of the artificial culture of the higher and lower filamentous 

 Fungi. He will be glad to receive suggestions from botanists 

 interested in the subject 



