CENTRAL SCIENTIFIC CO., CHICAGO. U. S. A. 



63 



B No. 854. 



No. 856. 



BALLOONS. Collodion, for hydrogen. 



Capacity, cc ". 250 500 1000 



Each .". $0.45 .60 .85 



S54. BALLOONS, Glass, very thin for weighing gases. Capacity, about 250 ec. 



Si yle A B C D 



Each 1.10 2.25 2.00 3.90 



85G. BALLOON, Glass, Dumas Type, for determining the specific gravity of vapors. Of very thin 

 blown glass. Capacity, about 200 cc 35 



858. BALLOON, Rubber, pure gum, diameter about 5 cm .06 



860. BALLOON, Rubber, pure gum, diameter about 15 cm 60 



BAROMETERS 



No. 876. 



No. 880. 



876. 



880 



BAROMETER, Aneroid. Sea Level Reading Type, with rearranged Weather Harks. This instru- 

 ment is arranged in such a manner that it is suitable for use in any location from sea level to 

 3,500 feet elevation. The adjustment is very simple and no derangement of the working parts 

 is necessary. Once adjusted for a given location by the observer, no further adjustment is re- 

 quired. A list showing altitudes of Meteorological Stations in the United States is furnished 

 with each barometer, and also a simple weather forecast card. 



To adjust the barometer for altitude for a given city, town or location, turn the brass plate set 

 in the back of the case (this is easily done with the fingers) until the number of feet corres- 

 ponding to the elevation of the city or town is opposite the arrow. The hand will then point 

 to the proper weather mark and the reading will be the same as that of the U. 8. Weather 

 Bureau, which is Sea Level Reading. 



Spun brass case, porcelain dial, 5 inches in diameter; adjustable stationary hand for marking the 

 last position of the movable hand 12.00 



BAROMETER, Aneroid. Same as No. 876, but with metal silvered dial and first quality com- 

 pensated movement 18.00 



BAROMETER, Aneroid, as adopted by the United States Xavy. A brass case barometer of extra 

 quality, with specially finished movement compensated for temperature, and silvered open 

 metal dial graduated to 0.02 inches. For altitudes up to 3,500 feet. Without altitude scale. 

 The best barometer of this stvle on the market 18.00 



