1H 



CHEMISTRY. 



experiments tluit seemed to prove a diminution of 

 chemical action resulting from limitations of space, 

 I'm!'. Liebrich. of Berlin, advanced as a deduction 

 the general proposition that liquids in proportion 

 as they are placed in confined spaces acquire, by 

 equilibric reactions, the properties of solids ; and 

 that friction in such fluids has a bearing of con- 

 siderable importance on chemical reaction. One of 

 the experiments was that of sinking a piece of 

 nickel, attached to a float, in water, and drawing it 

 down to the bottom of the vessel by magnetic at- 

 tract ion. The float did not again rise quite to the 

 surface, and this was attributed to friction in the 

 fluid. In a kindred experiment with two kinds of 

 glycerin, of different specific gravities, it was shown 

 by means of a specially constructed apparatus that 

 the lighter liquid did not rise quite to the surface 

 of the heavier if permitted to percolate through it. 



] jaws of the relations of the ions and the colors 

 of substances are deduced from experiments made 

 with reference to that subject by H. Carey Lea, as 

 follows : When highly colored inorganic substances 

 are composed of colorless ions, then if those sub- 

 stances can be brought into solution, the color 

 wholly disappears. No exceptions to this rule were 

 met with. It is thus proved that the ions have be- 

 come so far separated that they no longer influence 

 each other's vibrations. The union of ions, colored 

 and colorless, gives rise to the most surprising 

 changes of color. Two similarly colored ions may 

 unite to form a colorless substance. Two simi- 

 lar colorless ions may unite to form a strongly col- 

 ored substance. There is absolutely no relation 

 traceable between the color of an ion and that of 

 the substance which it forms. The change of color 

 of an acid indicator placed in contact with an al- 

 kali in no way depends upon dissociation. Disso- 

 ciation may result, but the change of color is inde- 

 pendent of it. Selective absorption of the visual 

 rays by a substance can never constitute a basis for 

 classification, but the relation of ions to the visual 

 rays leads to a classification which is in absolute har- 

 mony with the chemical characteristics of the ele- 

 ments. While there is good reason for believing 

 that in solution the ions are separated so as no 

 longer to affect each other's vibrations, it is also 

 certain that they remain within each other's range 

 of influence, so that they can not be considered as 

 free. 



The investigations of Runge and Paschen on the 

 spectrum of cleveite gas make the existence of an- 

 other new element besides helium seem to J. R. 

 Rydberg very probable. For this supposed new 

 element the name parhelium is suggested. In con- 

 nection with this subject Mr. Rydberg observes 

 that the supposed two elements of cleveite gas, as 

 well as argon, seem to suggest a regularity regard- 

 ing the atomic weights, the law of which may be 

 expressed : "If the atomic weights of the elements 

 which form the first rows of the periodic system 

 be reduced to the nearest uneven numbers, the 

 elements of uneven valency will have the form 

 4"- 1 , and the elements of even valency the form 

 4 n . On account of the uncertainty of the deter- 

 minations of atomic weights and their increasing 

 difference! from integral numbers, the rule could 

 be traced with some certainty only for the first 22 

 elements (to iron inclusive), 'it shows V:re 3 ex- 

 ceptions, viz. : Be (!) instead of 8), N (14 instead of 

 r> . and Sc (44 instead of 43) ; but it gives place for 

 'leliuin, 4) and A (argon. 20), as well as for an 

 element with the atomic weight 20, which would pos- 

 sibly answer to I'.i 'or parhelium). Spaces remain 

 for elements with the reduced atomic weights 36, 

 41. ami 47. Of the places formerly vacant in the 

 present division 2. Mr. Kydberg thinks, are prob- 

 ably permanently taken up by the new elements 



helium and argon. It seems possible that the pres- 

 ent exceptions may yet submit to the rule, when we 

 consider the imperfe'ction of our knowledge of the 

 rare earths and keep in view the surprising discov- 

 eries of the impurities of nitrogen. 



An investigation of the slow combustion of oxy- 

 gen and hydrogen, or the action of prolonged mod- 

 erate heating upon detonating gas, made by Victor 

 Meyer and Wilhelm Raum, bore reference to the 

 view advanced by the representatives of physical 

 chemistry, that a substance having a catalytic ac- 

 tion can not produce a reaction that is not already 

 existent, and that it merely increases the rapidity 

 of such a reaction. On this assumption hydrogen 

 and oxygen, which combine rather rapidly at 500 

 C., must combine to some extent at ordinary tem- 

 perature, even though this action may be so slow 

 that it would require hundreds or thousands of 

 years for the production of an amount of water 

 that could be detected, and that it is this slow ac- 

 tion that is increased to great rapidity by the pres- 

 ence of a catalytic agent, such as finely divided 

 platinum. The authors attacked the problem by 

 finding a temperature just so low that the gases did 

 not act appreciably for several days, then prolong- 

 ing the time of action at that temperature. It was 

 discovered that at 300 C. no water could be detected 

 after ten days' heating, but after heating uninter- 

 ruptedly for sixty-five days, water was found to 

 have been formed. The authors conclude from their 

 results that the reaction under consideration is re- 

 tarded but not stopped by lowering the tempera- 

 ture, and that the assumption of action at ordinary 

 temperatures is justified. 



New light has been found upon the origin of 

 Dalton's conception of the atomic theory by the 

 discovery at the rooms of the Literary and Philo- 

 sophical Society of Manchester of his laboratory and 

 lecture notebooks contained in a number of manu- 

 script volumes. It has hitherto been supposed that 

 it was the experimental discovery of the law of 

 atomic proportions which led Dalton, seeking for 

 an explanation of this fact, to the idea that chem- 

 ical combination consists in the approximation of 

 atoms of definite and characteristic weight the 

 atomic theory having, it is supposed, been thus 

 adopted to explain the facts ascertained by chemical 

 analysis. It now appears, as the matter is pre- 

 sented by Sir Henry Roscoe and Arthur Harden, 

 from the examination of Dalton's notes, that he was 

 probably led to his theory by an attempt to apply 

 the Newtonian doctrine of the atomic constitution 

 of matter to the explanation of the physical prop- 

 erties of gases, and more especially to the case of 

 the gases present in atmospheric air. 



A severe criticism of the periodic classification of 

 the elements as assuming to be a system or to repre- 

 sent a law has been made by Dr. Wyrouboff. If, 

 he says, the classification had remained what it was 

 at the outset that is, a very interesting and highly 

 ingenious table of the analogies and the dissimi- 

 larities of the simple bodies he would not have 

 questioned it. "But M. Mendeleef has aimed at 

 producing something more than a mere catalogue 

 raisonnee of the elements. He converted his classi- 

 fication into the periodic system. . . . He formu- 

 lated as the fundamental law of the physico-chem- 

 ical sciences the dictum that all the properties of 

 bodies are periodic functions of their atomic weights. 

 It would seem that, in view of a question so dis- 

 tinctly put, the first duty of the savant must be to 

 intervene, as has besn done with particular laws, to 

 check and verify them down to the utmost details. 

 This has not been done, not even dreamt of, and we 

 find, not merely in special researches, but even in 

 works of elementary instruction, the periodic law 

 accepted as a reality beyond all dispute. ... On 



