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TABLE OF DEW-POINT. 



a hygrometer. All that is reqiiired is to cut away a portion of the 

 wood on which the tube is mounted, so as freely to expose the bulb, 

 and to cover the latter with a fold of cambric, to which water must be 

 supplied by means of a few threads from a phial placed near. Of course 

 another thermometer, to indicate the temperature of the air, req[mres to 

 be suspended near to that with the wet bulb, and care must be taken 

 that, when dry, both mark the same degree of heat. To be quite 

 accurate the dry-bulb thermometer should be covered with a similar 

 piece of cambric, though this is hardly necessary, and may be incon- 

 venient where the syringe is so often used. 



The mode of using any wet bulb thermometer is explained by the 

 foUowing table and the remarks accompanjdng it, which were published 

 some years ago by Mr,' Wailes, of Newcastle. 



Table op the Dew-Point when the Temperatitre of the Air, in the Shade, 

 is between 55° and 100° of fahrenheit. 



