NOTES. 



575 



boiling paraffine, which destroys their capil- 

 larity, while it does not affect their conduct- 

 ing power. The superficial paraflBne may 

 be scraped off after the bath. Piles may be 

 obtained by this means that will endure in- 

 definitely, and have, apparently, an electro- 

 motive force superior to that of a Leclanche 

 pile of the same dimensions. — M. A. Blec- 

 NARD (translated for the Popular Science 

 Monthly from La Nature). 



Lightning withont Audible Thnnder.— 



A correspondent of " Nature " reports a vio- 

 lent rain and lightning storm which took 

 place near the crest of the Apennines, and 

 during which no sound of thunder was 

 heard. The writer also describes two other 

 such storms that he witnessed on the edge 

 of the Montenegrin highlands. " On these 

 nights," he states, " the lightning was so in- 

 cessant and vivid that we were able to walk 

 about, choosing our way among the stones 

 and shrubs as readily as by daylight, the 

 intervals between the flashes being, I should 

 judge, never more than a minute, while much 

 of the time they seemed absolutely continu- 

 ous, the landscape being visible in all de- 

 tails under a diffused violet light. Looking 

 overhead, the movements of the lightning 

 were easily discernible, the locality of the 

 discharges varying from one part of the 

 vault to another in a manner which it was 

 impossible to confound with the reflection 

 of lightning from a distance. Like the 

 storm of last night, those were followed by 

 copious rain, but not a single peal of thun- 

 der was heard during the whole night." 



Combustion • Prodncts from Different 



Lights. — The following figures show the 

 amount per hour of combustion-products 

 from several varieties of artificial light. Un- 

 less the electric light has some peculiar in- 

 jurious influence, it has a great superiority 

 on sanitary grounds : 



UGHT OY 100 CANDLES. 



Electric lamp, arc. . . 

 Electric lamp, incandescent 

 Gas, argiind-burncr . 

 Lamp, petroleum, flat flame 



Lamp, colza-oil 



Oanulo, paraiTine. . . . 

 Candle, tallow 



8 

 Si 



67-159 

 290-.S86 

 4860 

 72(10 

 6«00 

 92<10 

 9700 



NOTES. 



Mb. Robert E. C. Stearns, in a paper 

 read before the California Academy of Sci- 

 ences, announces his conclusion, from his 

 studies of the shells of the Colorado Desert 

 and the region farther cast (particularly 

 from studies of Physa and Anodonta), that 

 every item bearing upon the geoirraphical 

 distribution of the species indicates the 

 mountain-lakes as the sources whence they 

 are derived; points to their descent from 

 northerly regions as well as from higher 

 altitudes ; and contributes additional testi- 

 mony as to the antiquity of these widely 

 spread though inferior forms of life. 



General Richard D. Cctts, of the 

 United States Coast Survey, died in Wash- 

 ington, December 13th, in the seventy- 

 seventh year of his age. He had been con- 

 nected with the Coast Survey during the 

 greater part of his life, and was at the time 

 of his death first assistant superintendent 

 of the service, 



Ik a paper before the American Asso- 

 ciation on the "Serpentine of Staten Island, 

 N. Y.," Dr. T. Sterry Hunt expressed him- 

 self in favor of the opinion of Dr. Britton, 

 of the School of Mines, Columbia College, 

 that the belt containing the mineral is a 

 protruding portion of the Eozoic series. 

 The appearance of isolated hills and regions 

 of serpentine is common in other regions, 

 and is by Dr. Hunt explained by the consid- 

 eration that this very insoluble magnesian 

 silicate resists the atmospheric agencies 

 which dissolve limestones and convert 

 gneisses to clay — the removal of which 

 rocks leaves exposed the included beds and 

 lenticular masses of serpentine. Similar 

 appearances are seen in many parts of Italy, 

 where ridges and bosses of serpentine are 

 found protruding in the midst of Eocene 

 strata, and have hitherto, by most European 

 geologists, been regarded as eruptive masses 

 of Eocene age. Mather, who described the 

 Staten Island locality more than forty years 

 ago, also looked upon the serpentine as on 

 eruptive rock. 



A ccRiocs instance of the kindling of 

 a fire by means of the concentration of the 

 sun's rays by a globular water-bottle through 

 which they passed is related by a corre- 

 spondent of "La Nature." The day was 

 cold, but the sun shone brightly ; the bottle, 

 an " onion-shaped " flask, fillcl with water 

 so as to form a perfect lens, sat upon the 

 table. The starting of the fire, which would 

 have caused great damage if the relatcr of 

 the incident had not been present to extin- 

 p^uish it, was revealed by the smoke. A de- 

 liberate experiment was made on the next 

 day, with complete success, in kindling a fire 

 by this means. 



