298 



SCIENCE. 



[N. S. Vol. IX. No. 217. 



slightly the efficiency. Larger proportions of 

 these oxids are prejudicial, especially those of 

 neodymia and yttria. 



Commercial calcium carbid has, as is well 

 known, a reddish brown color. Moissan has 

 lately studied this color and finds that it is due 

 to the presence of iron, even traces of which 

 give it a decided tint. He finds, however, that 

 the pure calcium carbid crystals are colorless 

 and transparent. 



Apropos of the disputed occurrence of cop- 

 per as a normal constituent of plants. Pro- 

 fessor G. B. Frankforter, of the University 

 of Minnesota, describes, in the last Chemical 

 News, a very interesting occurrence of metal- 

 lic copper disseminated in the pores of an 

 oak tree in Minneapolis. The tree had died, 

 and, on cutting it up, the presence of copper was 

 so noticeable as to attract attention. Micro- 

 scopic examination showed that only the outer 

 annual rings contained an appreciable quantity 

 of the metal, which was in the form of fine 

 flakes, some of them 1.5 mm. in diameter. The 

 copper appeared to be very pure. It seemed as 

 if the tree had begun to absorb the metal only 

 in the last few years, and that this had occa- 

 sioned its death. The origin of the copper was 

 uncertain, though the soil is known to contain 

 native copper. The fact that the copper was 

 in the native state would raise the question as 

 to whether this is the usual form in which it 

 occurs in plants. Another question might be 

 raised as to whether plants take up any of the 

 copper which is so largely used in fungicides, 

 and as to whether this would eventually destroy 

 a tree on which it was used. 



Up to within a comparatively short time the 

 physical chemistry of solutions has been almost 

 confined to those in which the solvent is water. 

 Attention is now being turned to other solutions, 

 and very interesting questions arise as to the 

 applicability of the theory of electrolytic disso- 

 ciation and other theories which have been 

 worked out only with aqueous solutions. We 

 have already noticed in these columns the work 

 of E. C. Franklin, of the University of Kansas, 

 on liquid ammonia as a solvent. In the January 

 number of the Journal of Physical Chemistry, L. 

 Kahlenbergand A. T. Lincoln, of the University 

 of Wisconsin, detail a number of experiments 



with different non-aqueous solvents as to elec- 

 trical conductivity. The solvents used were 

 methyl and ethyl alcohol, acetone, ethyl aceto- 

 acetate, benzaldehyde, andnitro-benzene. The 

 substances dissolved were the chlorids of iron, 

 antimony, bismuth, arsenic, tin and phosphorus. 

 The molecular weights were also determined 

 by freezing point depression with nitrobenzene 

 as a solvent. The results obtained are not uni- 

 form enough, nor large enough in number, to 

 be used for any generalization, but the follow- 

 ing significant sentences occur at the close of 

 the paper : ' ' The general outlook at present 

 appears to be that, in order to harmonize the 

 molecular-weight determinations in many non- 

 aqueous solutions with the relatively high elec- 

 trical conductivity of the latter, the assumption 

 that combination between solvent and dissolved 

 substance takes place will have to be made. 

 Can it be true that, after its glorious success in ex- 

 plaining the properties of aqueous solutions of 

 acids, bases and salts, the dissociation thetry ivill 

 need the help of its old rival, the hydrate theory 

 {perhaps in a somewhat modified form), to explain 

 the facts in the case of non-aqueous solutions?" 

 The authors call attention to the ideas of Werner 

 regarding the existence of hydrated metal ions 

 in solution, a theory which partakes of the na- 

 ture of the two rival theories of solution. While 

 Werner's theory may be in many respects un- 

 satisfactory, it deserves to be better known 

 among chemists, and may foreshadow something 

 of the direction chemical thought will take, in 

 the development out of the present valence 

 theories. J. L. H. 



CURRENT NOTES ON METEOROLOGY. 



WATERSPOUTS OFF THE COAST OF NEW SOUTH 

 WALES. 



An incident quite unique in the history of 

 waterspout observation occurred on May 16, 

 1898, off" Eden, New South Wales. On this day 

 fourteen complete waterspouts, and six others, 

 more or less incomplete, occurred in the space 

 of five hours. It so happened that a mining 

 engineer, Mr. D. R. Crichton, was engaged in 

 making certain observations with a theodolite 

 in Eden at the time when the waterspouts be- 

 gan to form off"-shore. Mr. Crichton made the 

 most of his very exceptional opportunity ; 



