Some experiments on the changes which take place in the fixed principles of the egg during incubation.

  • William Prout
Date:
1822
Catalogue details

Licence: Public Domain Mark

Credit: Some experiments on the changes which take place in the fixed principles of the egg during incubation. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    tity of potash and soda,* and carbonates of potash and soda present. Finally, the proportion of the earthy phosphates to onei another was determined, and the quantities of the bases and acid obtained by calculation. The yelk of the egg is exceedingly difficult of combustion ; and indeed without proper precautions cannot be burnt at all, on account of the large quantity of phosphorus it contains ; which, by undergoing a partial combustion, forms a glassy coating that effectually excludes the contact of the air from the coal, and prevents its farther combustion. After a va- riety of attempts, the following were the two methods em- ployed. The yelk of an egg which had been boiled hard, and dried by exposure to the air, was rubbed in a mortar with a quantity of bicarbonate of potash. The mixture was then introduced into a platina crucible and exposed to a strong red heat, till the flame had ceased to escape from a small hole in the lid. The crucible being now removed from the fire, its contents, when cold, were again pulverised in a mortar with nitre. This mixture was then introduced a little at a time into the covered crucible till the whole was burnt. To the residuum distilled water was added, which of course took up every thing but the earthy phosphates, which were separated and weighed, while the alkaline solution, like that before mentioned obtained from the albumen, was submitted to the action of the appropriate re-agents, and thus the quan- tities of the different acids present ascertained. In this man- ner every thing was determined, except the proportion of alkaline matter present; and to ascertain this, other experi- * The quantity of soda equivalent to the sodium in union with the chlorine, was determined by calculation.
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