Januaey 26, 1900.] 



SCIENCE. 



153 



two equal portions, in one of which the lead is 

 precipitated as chromate and in the other cop- 

 per is determined by titration with potassium 

 cyanid. The filtrate from the fused sulfids is 

 acidified with acetic acid, filtered and the pre- 

 cipitate thoroughly washed and transferred to- 

 gether with the filter paper to a solution of 

 ferric chlorid, which is heated to the boiling 

 point and titrated with potassium bichromate. 

 Zinc is precipitated as sulfid in the filtrate from 

 the original sulfid precipitate, after adding 

 acetic acid and neutralizing the mineral acid 

 with sodium hydroxid. 



The second paper of the evening was read by 

 Dr. Fireman and was entitled : ' The Action of 

 Ammonium Chlorid upon Tetra- and Penta- 

 Chlorides, Preliminary Communication,' by P. 

 Fireman and E. G. Portuer. 



The last paper of the evening was read by 

 Mr. J. D. Tinsley and was entitled, ' On the 

 Estimation of the Water Soluble Constituents of 

 Soils,' by J. D. Tinsley and F. K. Cameron. 



Dr. Seaman spoke on the size of medicine 

 droppers found in the market. He had found 

 them variable, giving drops of diflferent sizes. 

 He showed that the size of the drop depends on 

 the external diameter of the orifice and not on 

 the thickness of the walls. 



Wm. H. Keug, 



Secretary. 



practical shape, in the form of stations located 

 at intervals of not more than a kilometer apart 

 in regions subject to hailstorms, and provided 

 with a small cannon placed vertically and sur- 

 mounted by a six-foot, narrow-conical trumpet, 

 which transmits the vortex and concussion of a 

 2-3 ounce charge of black powder to the threat- 

 ening cloud, preventing the formation of hail, 

 and apparently also diminishing the electrical 

 discharges. The idea originated with Burgomeis- 

 ter Moritz Stigel, of Styria, where after three 

 years' experience complete exemption from hail- 

 injury seems to have been secured, so that the 

 inhabitants have abandoned hail insurance, 

 finding the new method cheaper. 



In the last semi-annual volume of Proceed- 

 ings of the Academy of Georgifili, Florence, the 

 subject is once more extensively discussed. A 

 new style of breech-loading rapid-fire gun has 

 been substituted for the original Stigel pattern, 

 and 800 of these anti-hail stations have been 

 and are being established in the region of 

 Brescia, for the protection of vineyards. Small 

 bombs with time fuses have been added to the 

 equipnaient, and it is stated that the vortex, out- 

 lined by means of the dust, reaches the height 

 of two kilometers, and that its low, whistling 

 noise is heard from fourteen to seventeen 

 seconds after the discharge. 



E. W. HiLGARD. 



DISCUSSION AND COBBESPONDENCE. 



PREVENTION OF HAIL. 



But little notice has been taken in the United 

 States of the remarkable progress made in 

 northern Italy in the establishment of stations 

 for the protection against injury from hail- 

 storms, by means of the Wetterschiessen — one of 

 the old ' superstitions ' which has come to honor 

 again in our enlightened age. Shooting and ring- 

 ing of church bells has for ages been popularly 

 supposed to be efficacious against the efifects of 

 thunder-storms, especially of lightning. But 

 the belief found no scientific support, and sta- 

 tistics seemed to prove that the i-ains supposed 

 to follow the heavy cannonading of great battles 

 are, like the weather changes following those of 

 the moon, quite as much the exception as the 

 rule. Now, however, the matter has taken the 



ELECTRICAL ANESTHESIA. 



Editor of Science : My attention has 

 been called to an account in a New York 

 paper of the method of producing anaesthesia 

 by electricity, now being tried experimentally 

 in the Yale Psychological Laboratory. Permit 

 me to say that this account was entirely unau- 

 thorized. The demonstration of what had been 

 accomplished was made informally at the re- 

 cent meeting in New Haven of Section H of the 

 American Association for the Advancement of 

 Science, and no permission was given for any 

 publication of the results. The last authorized 

 statement in regard to the matter appeared in 

 Science for March 10, 1899 ; unless there is 

 some reason for the contrary, all future state- 

 ments will appear first in the columns of Sci- 

 ence. 



E. "W. Scripture. 



