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X. Observations on the Freezing of the Albumen of Eggs. By James Paget, Esq., 
Professor of Anatomy and Surgery to the Royal College of Surgeons of England. 
Communicated by Thomas Bell, Sec. R.S. 
Received September 26, 1849, — Read January 24th, 1850. 
In 1777> John Hunter communicated to the Royal Society a series of experiments 
on the heat of animals and vegetables, among which were some showing that an egg, 
after having been frozen and thawed, will, on a second exposure to cold, freeze more 
quickly than it did before, and more quickly than a fresh egg does when exposed to 
the same temperature. From these and other experiments, he concluded “ that a 
fresh egg has the power of resisting heat, cold and putrefaction in a degree equal to 
many of the more imperfect animals and he adds, “ it is more than probable this 
power arises from the same principle [/. e. a living principle] in both*.” Mr. Hun- 
ter’s pupils generally adopted this conclusion : and the facts on which it was based 
have formed a chief part of the evidence for the existence of a special vital principle 
capable of resisting, by a kind of passive opposition, the changes that physical forces 
produce in dead organic matter. 
In the course of some inquiries into the nature of the life of the blood, I repeated 
and extended Mr. Hunter’s experiments, and obtained results which, I venture to 
hope, may be deemed worthy of the consideration of the Society. 
My experiments consisted chiefly in submitting to temperatures near to zero of 
Fahrenheit, fowls’ eggs, into which thermometers with slender bulbs were intro- 
duced. The decrements of heat were registered every minute, and the time was 
noted at which each egg began to freeze, the general indication of that event being 
the swelling of the albumen, and its protrusion from the aperture through which the 
thermometer was passed. 
I found, as Mr. Hunter did, that a fresh egg generally resists freezing longer than 
one does which, having been previously frozen and thawed, is exposed, in all similar 
circumstances, to the same temperature. The result of twenty experiments, in which 
such eggs were placed in temperatures ranging from zero to 10°Fahr., was, that the 
fresh eggs were frozen, on an average, in 26 minutes, and the eggs that had been pre- 
viously frozen and thawed, were frozen for the second or third time in 15^ minutes. 
I next determined, by similar experiments, the respective times of freezing of fresh 
eggs, and of such as were variously changed in structure and chemical composition. 
Similar results appeared. If the yelks of the eggs were broken, so as to be mingled 
* Hunter’s Works, by Palmer, vol. iv. p. 150. 
