DR DAVY ON THE FREEZING OF THE EGG OF THE COMMON FOWL. 507 



the other. During the night, the thermometer was as low as 24°; at 8-30 a.m. 

 on the 25th, it was at 25°. Both eggs were found ruptured, the fracture extend- 

 ing from the small end towards the large ; if there were any difference, the 

 gummed egg was most ruptured. The shell removed, the albumen of each pre- 

 sented the same crystalline and cellular appearance as that of the day preceding. 

 The yolk of one egg was 27*5^ ; the white 31°; of the other, the gummed, the 

 yolk was 29°, the white 31°. These temperatures were ascertained when the 

 temperature of the open air had risen to 35°. 



4. On the night of the 25th, two newly laid eggs were exposed, one of them 

 smeared with butter. During the night the thermometer was as low as 19°. 

 At 8-30 A.M., on the 26th, it was at 20°. Both eggs were found fractured, the 

 smeared one, at about equal distance from both ends, the other at both ends. At 

 1115 A.M., when the thermometer in the open air had risen to 30°, the tempera- 

 ture of the smeared one at its surface within the shell was 31-5°; deeper, 3F; 

 that of the other, in the albumen, just within the shell, was 30-5°; deeper, 30° ; 

 it was more firmly frozen than that smeared with butter, and this throughout. 



These two trials were made on the idea (not supported by the results), that 

 the coating of one of the eggs might greatly retard or prevent its freezing. 



5. On the 26th, two eggs were exposed, one taken from lime-water, where it 

 had been kept about twelve months ; the other, laid the same day ; both sank in 

 water. Their temperature, ascertained before exposure by a thermometer intro- 

 duced through a small hole, made about midway between the two ends, in the 

 newly laid was 45-5° ; in the other 46°, this within doors. At 10-3° a.m., they 

 were placed on moss in the open air, the thermometer close by 26°. At 1024 

 A.M., when the open air was 32°, that of each egg was 39°. At 10-40, the air 34°, 

 that of the fresh egg was 35° ; of the other 365. At 1*10 p.m., when the open air 

 was 44°, that of the fresh egg was 40°, that of the other 38-5. These results do 

 not appear congruous, I give them as obtained. They may at least tend to show 

 the obscurity of the subject. 



6. On the night of the 26th, other two eggs were exposed, one from lime- 

 water, the other newly laid ; both sank in water. Most of the time the sky was 

 overcast. At 8*30 a.m., on the 27th, the thermometer was 31°. Both eggs were 

 free from fracture, and it may be inferred were not frozen. All the while, from 

 the 22d to the 25th, a calm prevailed, and the sky at night was unusually clear. 



The newly laid egg which had been exposed in the last experiment to a tem- 

 perature of 31°, on the 27th was put under a hen that had been sitting since the 

 19th of February. On the 10th of March, when most of ten eggs were hatched 

 (six out of nine), the egg in question was taken from under her and examined. 

 The foetal chick was found well-developed for the period, and was evidently alive 

 when removed warm from the nest.* 



* The foetus, well detached from the vitellus and the membrane, weighed 27 3 grs. The allantois 



