

water heats expands the other extinguisher rises 

 and promptly puts out the other light, and still the 

 heat remains unchanged in the egg chamber. 

 Suppose both lights go out, for want of oil ; the 

 thirty gallons of water, packed with an inch of 

 hair felting all around and over it, as it is, in a 

 double cased machine, packed with the same in- 

 sulating material, does not lose more than one or 

 two degrees of heat during the whole night. [/$ a 

 person likely to Jill one lamp and forget the other, if 

 both are together? If you forgot to attach one ex 

 tinguisher on a very warm day, you would risk 

 spoiling the eggs, as the turning down of one flame 

 would not compensate for the one at full blast at the 

 latter part of a hatch. A person who has not time 

 and memory to fill the lamp or lamps once in 24. 

 hours should not use an incubator .] Now an incu- 

 bator has got to be run three weeks, night and day. 

 All of the above mistakes often occur through the 

 carelessness, forgetfulness or inexperience of the at- 

 tendant ; so that the superiority and safety of our 

 regulation above all others is manifest. The 

 superiority of this principle of regulation over 

 that on hot air machines is manifest. [ We fail to 

 see it.~\ Their only means of reducing heat is by 

 ventilating when the heat is excessive ; [ This, if 

 applied to the heat in the egg chamber (and thai is 

 the vital place}, is a mistake or a misstatement, as 

 the best hot air incubators do not regulate the tem- 

 perature of the egg chamber by opening and closing 

 ventilators therein or therefrom it is the Hot 

 Water machines that do that. The hot-air machine 

 97 



