March 4, 1904.] 



SCIENCE. 



395 



having recourse to what Mendeleef denomi- 

 nates the metachemical and vague (' ver- 

 schv?ommene ') theory of electrons. The radio- 

 active atoms, with their high atomic weights, 

 possess, as large centers of mass, the power of 

 holding a relatively large number of ether 

 atoms, though there is no chemical combina- 

 tion. The entrance and exit of these ether 

 molecules from the groups is accompanied 

 by those disturbances of the ethereal medium 

 which cause the rays of light. The phosphor- 

 escence of bodies immersed in liquid air is 

 caused by the increased absorption and con- 

 densation of ether molecules at low tempera- 

 tures. The original article contains many 

 other suggestive thoughts, such as the proba- 

 bility of a fifth halogen element, with- atomic 

 weight of about three, corresponding to the 

 fifth metal of the alkalies. 



ATMOSPHERIC CORROSION OF ZINC. 



A STUDY of the action of the atmosphere 

 upon zinc has recently appeared in the Pro- 

 ceedings of the Chemical Society (London), 

 by G. T. Moody. Strips of thin sheet zinc 

 were exposed for five months to the action of 

 the atmosphere, with the result that the metal 

 became completely covered with a half-ciystal- 

 line coating of a basic carbonate, of formula 

 ZnCOj, 3Zn(0H),. From this it appears that 

 the corrosion is to be ascribed, not to a direct 

 oxidation, but to the action of the atmospheric 

 carbonic acid. A confirmation of this was 

 found in the fact that zinc dissolved in a 

 saturated solution of carbon dioxid, the acid 

 carbonate of zinc being formed, and on spon- 

 taneous evaporation a precipitate of basic 

 carbonate was formed, of the same composi- 

 tion as that occasioned by atmospheric cor- 

 rosion. While commercial hydrogen peroxid 

 has a very rapid action on zinc, converting it 

 into the hydroxid, pure hydrogen peroxid, even 

 of thirty per cent, strength, is entirely without 

 action, and the same is true regarding iron. 

 Lead, on the other hand, is rapidly acted on 

 by this reagent, being converted superficially 

 into lead peroxid. Thus the action of the 

 atmosphere on lead may be due to the pres- 

 ence of hydrogen peroxid, but this can not be 

 the case with the corrosion of zinc and iron. 



That zinc is less corroded in the atmosphere 

 than iron is attributed by Moody to the fact 

 that so much of the carbonic acid is retained 

 by the zinc in the form of basic carbonate, 

 while in iron the carbonic acid is set free as 

 soon as it has done its work, and thus keeps 

 on in its attack upon the iron. 



J. L. H. 



CURRENT NOTES ON METEOROLOGY. 



METEOROLOGICAL PHENOMENA OF THE MONT 



PELEE ERUPTION, JULY 9, 1902. 



In the Popular Science Monthly for Jan- 

 uary, Professor T. A. Jaggar gives an account 

 of the eruption of Pelee on July 9, 1902, in 

 which several of the meteorological phenom- 

 ena associated with the eruption are noted. 

 One of the most striking features of the ex- 

 plosion was a great column of steam ob- 

 served at 8 A.M. on July 11. "A vertical 

 pufi from the volcano rose 10,000 feet into 

 the air, showing at first superb gray-brown 

 caulifiower surfaces, and later taking on 

 smooth outlines, with a funnel-shape and a 

 feathery fringe." A similar steam column 

 was observed on July 16, and a fine photo- 

 graph was taken of it. The height of this 

 latter column was between four and six miles. 

 As clearly seen in the photograph, the upper 

 part of the cloud was turned towards the east, 

 showing the effect of the anti-trades. On 

 July 9 the tops of a number of cumulus 

 ( ? cumulo-nimbus) clouds were seen to be far 

 below the black dome of volcanic dust. The 

 dust in the air gave the moon a dim reddish- 

 yellow appearance. ISTo strong indraft of air 

 towards the volcano was noted. 



DEMTSCHINSKy's LONG-RANGE FORECASTS. 



In the journal Climat, the publication of 

 which was begun in 1901, and to which refer- 

 ence has been made in these notes, Demt- 

 schinsky, a Russian engineer, has been making 

 public long-range weather forecasts, based 

 chiefly on supposed lunar influences. These 

 forecasts and the method used by Demt- 

 schinsky in making them, have lately been 

 subjected to a critical study by Professor 

 Klossovsky, of Odessa, the director of the 

 Meteorological Service of southwestern Russia 



