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Advanced Bcc Culture. 



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Heating air increases its power of absorption, hence we enjo)' a fire on 

 a damp day. If the air of a cellar is dry, it will be readily seen that 



the temperature may be allowed to 

 go much lower. In other words, a 

 cold dry atmosphere or a damp 

 warm one may be about equal, so 

 far as effects are concerned. This 

 is a point that bee-keepers have not 

 sufficient!}' considered. 



W'e have many reports of the 

 successful wintering of bees at such 

 a degree of temperature, but noth- 

 ing is ever said as to the degree of 

 saturation. Ree-keepers ought to 

 use a wet-bulb thermometer in their 

 cellars ; then let the degree of satur- 

 ation he given with that of the 

 temperature, and we would have 

 something approaching accuracy. 

 I say "approaching accurac}*," be- 

 cause the strength of the colonies and the manner in which they are 

 protected have a bearing. A populous, well-protected colony can warm 

 up the inside of the hive, expelling the moisture and increasing the 

 absorbing capacity of the air. Building a fire in a room on a damp 

 day is the same thing in principle. 



As mentioned in the preceding paragraph, the way to decide in 

 regard to the amount of moisture in the air is by the use nf a wet-bulb 

 thermometer. The arrangement is very simple, and any of my readers 

 could make one. Attach two ordinary thermometers, side by side, to 

 a piece of board. Just below them fasten a tin cup for holding water. 

 Alake a light covering of candle-wicking for one of the bulbs at the 

 bottom of the thermometer, allowing the wicking to extend down into 

 the water in the cup. The water will ascend the wicking and keep the 

 bulb constantly wet. There will be, of course, evaporation from the 

 wicls surrounding the bulb. Evaporation causes a li iss of heat ; hence, 

 the drier the air the greater the evaporation, the greater the loss of 

 heat, and the lower will go the mercury in the wet-bulb thermometer. 

 The greater the difference in the readings of the wet and the dr\' bulb 

 thermometers, the drier the air. In the open air there is sometimes a 

 difference of 26 degrees; but this is unusual. Alien it is raining the 

 air is then saturated. There is then no evaporation, and both thermom- 

 eters show the same degree of temperature. In the cellar in which I 

 used the wet-bulb thermometer the diff'erence in the readings of the two 



