Aug. 3, 1908.] Agricultural Gazette of N.S.W. 



645 



generally. To apply water in these incubators a small tray can be found to 

 use, or simply throw the water into the chamber or on the floor under the 

 machine. A helpful guide as to the need or not of artificial moisture is the 

 chart shown in the illustration. This chart is a gauge of the air-cell, the 



Hen-egg. 



Duck-egg. 



empty space on the top of the eg^,, which increases during hatching, and on 

 the days named the contents of the greater number of eggs should be about 

 down to the mark. If below same, moisture should be supplied or the 

 ventilators closed a little. If above the date, the eggs have not been aired 

 sufficiently or the germs are weak. More turning and airing now is required, 

 and the hatch will often run a day or two overdue. It has been advocated 

 to practise rolling the eggs gently in this case, but it is too much labour where 

 a large number of eggs are being hatched. The amount of water used is 

 about an ordinary tea-cupful to 100 eggs. 



The Thermometer. — There are two ways of placing same : hung from the 

 top of the hatching chamber, in the centre, with the bulb just on a level with 

 the eggs, or the thermometer resting on the eggs, with the bulb on two eggs. 

 The former method is by far the most convenient, especially at hatching time, 

 and the other way has no apparent benefit on results. 



Testing for Fertility is best done on the fifth day, the germ being very 

 fragile before that date. The leather tester, the size of an egg at one end 

 and large enough to cover both eyes at the other end, is used for testing with 

 sunlight. The egg should be held in position below the level of the face, and 

 the sunlight allowed to shine on it. For night testing, a tester is often 



