Spirit of Philosophical Discovery. 



552 



Tlie Rjghl Hoii. Geokob Knox has 

 made experiments for detaching hilumeji 

 from a great variety of mineral sub- 

 stances: from vvlience he concludes, 

 that nearly all the minerals classed by 

 M. Werner under the denomination of 

 the na?(z-trap formation, contain notable 

 quantities of bitumen; and smaller pro- 

 portions of the same substance he was, 

 but with diflBculty, able to detach from 

 several minerals belonging to the older 

 Wernerian formations. The author 

 concludes with an important caution to 

 ex[)erimenters, viz. " the loss of weigiit 

 by ignition, generally esteemed as wa- 

 ter, may, in reality, be partly owing lo 

 the expulsion of bitumen." 



Dr. Arnott has been successful in 

 his treatment of several cases of pulmo- 

 nary disease, chiedy through causing 

 uniformity of temperature, and the pre- 

 vention of draughts of cold air in the 

 winter apartments occupied by his pa- 

 tients. This he effects by enelosiug the 

 -front of the fire-place with glazed doors, 

 the frames of wliich are lightly con- 

 structed of metal, which when shut 

 closely encase the fire, and prevent its 

 supply of air being drawn from (he room. 

 A pipe of proper size, laid from some 

 outer room or the street, and furnished 

 with an adjustable opening beneath the 

 iire, supplies (he necessary cold air, 

 without the same communicating with 

 the room, whilst the fire is being stirred 

 or supplied with coals, or when the fire 

 is disused. By this means a large room 

 may by one fire be maintained in a com- 

 fortable and equal degree of heat in 

 every part of it, with, the doctor asserts, 

 a saving of one-half of the usual fuel, 

 the prevention of dust in the room. Sec. 



The welding of cast steel to itself or to 

 iron, at a heat little above a red heat, 

 which low temperature is essential to- 

 wards preserving the quality of the 

 steel, has long been known and prac- 

 tised as a secret by Mr. Augustus 

 Seibe, of London. If is thus effected : 

 — In a clean crucible borax is melted, 

 and then with it one-tenth of its weight 6f 

 pounded sal-ammoniac 's mixed, and 

 incorporated over the fire: the mixture 

 IS then poured out on to an iron plate, 

 and, when cold, this glass-like substance 

 is pulverized, and mixed with an equal 

 weight of unslacked lime, and preserved 

 for use. The pieces of steel or iron in- 

 tended to be joined, being raised to a 

 low red heat, are to have their surfaces 

 strewed over with the above mixture, 

 which will melt and run over them like 



[July 1, 



sealing-wax. These pieces are then to 

 be returned to the fire, and further 

 heated, but not nearly to the usual %veld- 

 ing heat; and quickly, on wilhdrawiu!^ 

 them, they are to be joined and beateu 

 by the hammer, until the welding is per- 

 fect. — Register of Arts, No. 1. 



The ignus fatuus, or will-o'-the-wisp, 

 has of late years been considered by 

 writers as occasioned by portions of 

 some plios])horic gas, rising from stag- 

 nant and putrid pools or marshes, 

 church-yards, &e. anddrihing before the 

 wind in a state of spontaneous ignition; 

 but some serious doubts have been 

 thrown on this explanation, in the Me- 

 chanic's Magazine, No. 8, and the sug- 

 gestion offered, that some rather rare, 

 large, flying insect, which occasionally 

 possesses far greater liiminnsity than 

 the glow-worm, gives rise, during its 

 short and low flights, to the appearance 

 in question. It is desirable that country 

 persons, residing or frequently passing 

 near to spots where will-o'-tlic-vvisp i? 

 often seen, would note down in writing 

 the day and hour of every such occur- 

 rence, and, afler continuitig this through 

 a year, that they woidd add t(j sucli 

 notes descriptions of the spots, with re- 

 spect to the nearest roads, houses, and 

 villages, by bearings and distances, and 

 transmit these to ours or some other 

 journal, the publication of wliich would 

 enable any naturalist of the distiict to 

 visit the sjiot.*^, and make arrangements 

 for watching at the most likely times 

 for succeeding, in observing the pheno- 

 menon, and catching the luminous in- 

 sect, if any such should appear to be 

 present. 



The hardness and smell of soaps have 

 their origin and modifications in certain 

 chemical principles, which it has lately 

 been the object of M. Chevreul lo 

 discover, and thereby to improve the 

 manufacture of this essential article in 

 domestic economy, and in surgery and 

 the arts. These experiments arc (leiail- 

 ed in vol.xxiii. of the Ann. de Chim. 



The strength of vinous liquors improve 

 hy evaporation, when covered by bladder. 

 According to the experiments of Dr. 

 SuMMERiNO, alcohol M'jll not pass 

 through those insensible pores in a 

 bladder which freely swffcr water to 

 pass, and that, owing to this proi>erty, 

 spirits of wine may be highly rectified, 

 by exposing it in a bladder to a current 

 of dry air, whereby a rapid evaporation 

 of the watery parts of the spirit may be 

 effected... Cyprus wine, in a bladder 



thus 



