212 POULTRY BREEDING 
supplied by pouring water on a tray of sand under the 
egg tray, the sand tray covering the whole bottom of the 
incubator. In the machines without moisture a similar 
tray of dry sand was kept.’ 
“After giving tables on maximum moisture, medium 
moisture and non-moisture machines the following is 
given: 
““Tt will appear from a study of these tables that nearly 
100 per cent better hatches were obtained by the use of 
moisture, and there was no contradiction in all the tests.’ 
Under the ‘Weight of Chicks’ the following results were 
found which show that the weight of the chicks varied 
with the method of hatching: ‘In the machines supplied 
with maximum moisture the chicks weighed 1.185 ounces; 
in medium moisture machines, 1.159 ounces; in non-mois- 
ture machines, 1.072 ounces. Hen-hatched chicks weighed 
1.258 ounces. The results of these weighings would in- 
dicate that vigor in chicks demands a greater amount of 
moisture during incubation than the incubator as at pres- 
ent made can furnish.’ 
“On moisture and germ development another point is 
verified in favor of the ‘hatchability’ of the moisture ma- 
chines. Prof. Dryden says: 
““Another point has been brought out in the moisture 
tests. The evidence is somewhat contradictory, but our 
tests seem to indicate that proper germ development can 
not take place where the proper conditions of humidity do 
not exist. Our records show that a larger number of 
eggs were tested out of the dry machines as infertile or 
dead than out of the moist machines.’ 
“Further under the heading ‘Evaporation of Eggs’ this 
statement is made: ‘It is plain that artificial incubation is 
faulty where it does not more closely approach the con- 
