202 ANNUAL OF SCIENTIFIC DISCOVERY. 



the cause of it must be some general law entirely distinct from local situation. 

 "What is that law? "It arises from the atmospheric pressure," answers the 

 Academy of Sciences. "When," it continues, "the barometric column rises, 

 smoke and pernicious emanations rapidly evaporate in space. In the con- 

 trary case we see that smoke and pernicious vapors remain in apartments and 

 on the surface of the soil. Now, every one knows, that of all winds, that 

 which causes the greatest ascension of the baronietric column is that of the 

 east, and that that which lowers it most is the west. "When the latter blows, 

 it has the inconvenience of carrying with it to the eastern parts of a town all 

 the deleterious gases which it meets in its passage over the western parts. It 

 results from that that the inhabitants of the eastern part of a town have to 

 support not only their own smoke and miasma, but those of the western part 

 of the town, brought to them by the western winds. When, on the con- 

 trary, the east wind blows, it purifies the air by causing to ascend the per- 

 nicious emanations which it can not drive to the west. Consequently, the in- 

 habitants of the west receive pure air from whatever part of the horizon it 

 may arrive ; and it may be added that, as the west winds are those which 

 most frequently prevail, they are the first to receive the air pure, and as it 

 arrives from the country." After thus explaining why the western parts are 

 the best, the Academy makes these recommendations: 1. That persons who 

 have the liberty of choice, and especially those of delicate health, should 

 reside in the ^western parts of towns. 2. That all establishments from which 

 emanate pernicious vapors and gases should be placed in the east. 3. That 

 in building a house in a town, and even in the country, the kitchens and other 

 dependencies from which pernicious emanations may arise should be placed 

 to the east. The members of the Academy who have announced the preced- 

 ing discovery, and made the preceding recommendations, are Messrs. Pelouze, 

 Pouillet, Boussingault, and Elie de Beaumont all of them of European 

 reputation as savants. 



* 



ON CERTAIN CURIOUS MOTIONS OBSERVABLE ON THE SURFACES 

 OF WINE AND OTHER ALCOHOLIC LIQUORS. 



The following is an abstract of a paper on the above subject read at the 

 last meeting of the British Association by Mr. J. Thomson : The phenomena 

 of capillary attraction in liquids are accounted for, according to the generally 

 received theory of Dr. Young, by the existence of forces equivalent to a ten- 

 sion of the surface of the liquid, uniform in all directions, and independent 

 of the form of the surface. The tensile force is not the same in different 

 liquids. Thus it is found to be much less in alcohol than in water. This fact 

 affords an explanation of several very curious motions observable, under 

 various circumstances, at the surfaces of alcoholic liquors. One part of these 

 phenomena is, that if, in the middle of the surface of a glass of water, a small 

 quantity of alcohol, or strong spirituous liquor, be gently introduced, a rapid 

 rushing of the surface is found to occur outward from the place where the 

 spirit is introduced. It is made more apparent if fine powder be dusted on 

 the surface of the water. Another psrt (f the phenomena \?, that if the sides 



