549 Royal Society. 



quickly, but may be reduced to 16° or lower ; then, at the instant of 

 beginning to freeze, their temperature rises to 32°. 



That this peculiarity of fresh eggs is not due to vital properties, 

 is proved by experiments vi^hich show that certain injuries, such as 

 mechanical violence, addition of water, and others, which spoil their 

 powers of resisting freezing, do not prevent eggs from being deve- 

 loped in incubation. By the same and other experiments, which are 

 related, it is made probable that the peculiarity depends on the me- 

 chanical properties of the albumen ; for, whatever makes the albumen 

 more liquid than it is naturally in the fresh egg, destroys the power 

 of resisting freezing. 



The author could find no other substance possessing this property ; 

 and in evidence of its adaptation to the purpose of preserving eggs 

 from the loss of their capacity of developement, which they would 

 suffer in being frozen, he relates experiments in which eggs were 

 kept for a considerable time at temperatures ranging from zero to 10° 

 Fahr., yet were afterwards developed in incubation. By the same 

 series of experiments it was shown, that, although freezing renders 

 the effectual developement of the germ impossible, yet the intensest 

 cold, if freezing does not take place, has no similar result. 



2. A Letter from M. Kupffer, to Lieut.-Col. Sabine, For. Sec. 

 R.S., "On the establishment of a Central Physical Observatory at 

 St. Petersburg." Communicated by Lieut.-Col. Sabine. 



3. A Letter from Captain C. M. Elliot, Madras Engineers, to 

 Lieut.-Col. Sabine, For. Sec. R.S., transmitted through the Court 

 of Directors of the East India Company. Communicated by Lieut.- 

 Col. Sabine. 



Having undertaken the magnetic survey of the Indian Archipelago 

 at the recommendation of the Royal Society, I think a slight sketch, 

 detailed as briefly as possible, of my operations may not be unin- 

 teresting to Sir John Herschel and the Committee of Physics of 

 which he is Chairman, prior to the publication of the Survey. I 

 trust likewise I have acted strictly in accordance with the wishes of 

 those who so kindly recommended me for the Survey, and I hope 

 that my earnest efforts to do my duty will gain for me that appro- 

 bation which I have under no ordinary difficulties incessantly striven 

 to obtain. 



I will in the first place mention the different stations I visited, and 

 then describe in a few words, the way in which the observations were 

 taken. 



I have made a most complete survey of Java. At Batavia I 

 established an observatory where observations, magnetic and meteoro- 

 logical, were taken hourly from 3 a.m. to 9 p.m. for nine months. 

 In addition, about fifty stations, where observations of dip, of total 

 intensity, of latitude, longitude, and declination were taken ; these 

 were always made by myself, and I am certain they can be depended 

 upon. 



In Borneo an observatory was established at Sarawak, where ob- 

 servations were taken quarter-hourly for three months, besides visiting 



