| Show tho ali meter the amount of moisture present or tho the humidity of the air is determined detent by a comparison com pariton of dry and slid wet bulb thermometers they are both ordinary 0 but the bulb of the latter is creeed with muslin that ie Is wet in tho the latest form of instrument the ther momet erg are mounted on anni arms carried by a t that if Is rotated A by a crank which is geared to tho the ab ebitt af L the wo tion of the haft shaft rotate rotates mhd thermometer in vertical planes aud and causes the water li ithe he muslin to more or lea rapidly according to the amount in the air this evaporation lower lowers the tempera tore of the ther niona eter and from table tables constructed after long experiments te tle agree of mul moisture sture ran ean bo be de tennin ly by tt difference in temperature between alo two th thermond ermons aters et eraB M J prindle in popular set Bc |
