08 ANNUAL KECORD OF SCIENCE AND INDUSTRY. 



urea are the most refined of modern times. He attains an 

 accuracy of the twenty-five-hundredth part of an inch, in his 

 results rivalling the new normal barometer constructed by- 

 Wild. 



There have come to hand from the India Office Blanford's 

 pamphlets of Instructions to Observers and Tables for the 

 Use of Observers, both of which correspond in every way with 

 the latest views of meteorologists. We note as to his tables 

 for the psychrometer that Blanford has computed them for 

 barometric pressures of from 29.7 to IS inches, thus allowing 

 the use at each station of a table adapted to its own altitude. 

 He lias also introduced the correction to the tension of vapor 

 for reducing barometric heights to gravity at 45 latitude, 

 a correction that is quite sensible, but ought not to be ap- 

 plied unless all the barometric readings are similarly correct- 

 ed, as has been done by Ferrel in the isobars on his charts of 

 the earth on a polar projection. 



Professor Mendelleff, of St. Petersburg, author of a well- 

 known hand-book of chemistry, has announced his intention 

 to devote to the prosecution of atmospheric studies by means 

 of balloons all the profits of his published works for the next 

 five years. He will probably begin by constructing a cap- 

 tive balloon holding from 50,000 to 70,000 cubic feet of gas. 



Some interesting facts deduced from observations made 

 during balloon voyages near Nashville, Tennessee, under the 

 conduct of the well-known aeronaut Professor S. A. King, 

 of Boston, are given in the Signal Office Monthly Weather 

 Reviews during the year. 



The highly important observations of clouds and currents 

 of wind by means of toy balloons continue to be daily made 

 at Paris, under the patronage of Secretan. No more prom- 

 ising field of research has of late years been opened up to 

 meteorologists, and its economy places it within every one's 

 reach. 



Bell's telephone proves to be so exceedingly sensitive to 

 disturbing: currents that it is said that the occurrence of a 

 thunder-storm anywhere within the horizon was made evi- 

 dent by a peculiar class of noises indeed, storms still out 

 of sight have thus preannounced their approach, and it is 

 suggested that this instrument may prove a highly useful 

 addition to the equipment of the meteorological observer. 



