770 TRANSACTIONS OF SECTION M. 
2. The Artificial Incubating Establishments of the Egyptians. 
By W. H. Capmany, B.Sc., F.C.S. 
The art of hatching fowls’ eggs by artificial heat originated in Egypt in very 
remote times and was introduced into Europe from Egypt as a result of 
observations made by some of the scientific members of Napoleon’s expedition. 
The Egyptians have long been famous for this practice and still successfully 
carry it out throughout the country on a large scale. The profession is 
traditionally transmitted from father to son, and is consequently confined to 
particular families. The secrets of the process are generally guarded with a 
religious zeal, and solemn oaths are taken not to divulge them. This largely 
accounts for the very imperfect descriptions of Egyptian incubators published 
up to date, and the entire absence of all details of working. The author has 
resided for the last eight years in close proximity to several of these establish- 
ments, and has been able to examine both the buildings and the details of 
working. The building is large, and usually contains several rooms in which 
the attendants live, in addition to the egg-ovens; it is generally rectangular 
in shape and constructed of sun-dried Nile mud bricks. The walls are ot 
double thickness with layers of sand between. A vaulted passage divides the 
two parallel rows of ovens. Each egg-oven has a capacity of about 30 cubic 
metres, and consists of two cells or compartments, one above the other, com- 
municating by an opening in the middle of the lower roof. There is also a 
dome-shaped opening in the upper roof for the escape of smoke. Each cell 
can be entered from the passage by an opening just large enough for a man 
to pass through. The buildings vary in size, usually containing from eight to 
twenty ovens each. 
The incubators are worked for four or five months of the year only, in 
winter and in spring. 
Method of Working.—The ovens are heated a few days before putting in 
the eggs by means of burning fuel on the floors and in the passage. Chopped 
bean-straw or dried cakes of cattle-dung serve as the fuel. After removing the 
ashes and smoke from the lower cells, the floors of these are covered with straw 
mats sprinkled with bran, and the eggs are piled on these mats; each oven 
takes about 7,000 eggs. 
The proper temperature is maintained by adding glowing fuel to the troughs 
in the upper cells. The eggs are pushed by hand round the floor twice daily so as 
to be heated from above in rotation. This device of heating from above is 
presumably adopted in imitation of the processes that occur with the sitting 
hen. At the end of seven days the eggs are tested with olive-oil lamps and 
clear (i.e., unfertile) ones removed. After eleven days all fire is removed, and 
the upper cel] is cleaned, and for the last seven days half the eggs are trans- 
ferred to the upper cells and placed on mats. During the last ten days the 
temperature is maintained by the heat given out by the chicks themselves as 
they develop within the egg. The temperature and aeration are regulated by 
attending to the roof openings and fuel supply. Thermometers are never used. 
Long experience enables the superintendent to tell the exact temperature 
necessary by placing the egg against the sensitive skin of his eyelid. The 
variation in temperature during the hatching period is very slight as shown 
op the temperature chart obtained by a self-registering thermometer. The 
period of hatching is twenty-one days, the same as required for natural 
incubation. 
The chicks, as soon as hatched, are removed to the passage to dry and 
disposed of on the following day, no food being required. 
The hen hatches without additional moisture and equally so the egg-ovens 
of Egypt. The relative humidity has been taken daily to show the hygro- 
metric state of the air in the cells during incubation. 
Chemical analyses of the gaseous products resulting from the fuel combus- 
tion have been made by the author, and the effects of these products in the 
egg-cells were discussed with reference to Dr. Bay’s remarkable theory recently 
communicated to the ‘Institut Egyptien,’ viz., that the presence of carbon 
dioxide is necessary during the incubation period and indispensable to the 
evolution of fatal life. 
On September 14, 1911, there were 512 native chicken incubators in the 
