396 Analysis of Scientific Books. 



series of experiments on the vegetation of this fungus, which 

 show that it grows luxuriantly when embedded in snow at a 

 temperature considerably below 32°; and that although exposure 

 to the sharp air and wind sometimes kills the primitive fungi, 

 their seeds retain sufficient vitality to vegetate and propagate 

 under snow, which seems to be their natural soil. It is to be 

 regretted that the plate annexed to this paper was not coloured 

 after Mr. Bauer's original drawing. 



iv. On the Errors in Longitude, as determined by Chronometers at 

 Sea, arising from the Action of the Iron in the Ships vpon the 

 Chronometers, By George Fisher, Esq. 



The observations contained in this paper are important, as 

 connected with the chronometrical determination of the longi- 

 tude ; and the perspicuity with which they are detailed does 

 much credit to the author. 



The sudden alteration in the rates of chronometers when 

 taken on ship-board has generally been ascribed to the motion 

 of the vessel, and frequently noticed by intelligent seamen. 

 Mr. Fisher accompanied Captain Buchan in his voyage to Spitz- 

 bergen in the summer of 1818, and soon after the arrival of the 

 ships off that coast, the chronometers on board the Dorothea 

 were found to be rapidly gaining on their original rates in London, 

 hence the land appeared westward of its true position as deter- 

 mined by lunar observation. On the 9th of August the chro- 

 nometers were landed upon an island, and their acceleration 

 immediately ceased. The loss in the rate on shore amounted 

 in some cases to no less than 13 or 14 seconds daily; in some 

 tiie change was sudden, in others more slow, but it was in- 

 variably found to take place. 



This acceleration is not peculiar to high latitudes, for several 

 chronometers put on board in the river with losing rates, were 

 found to having gaining rates when the ships arrived at Shet- 

 land. Having adduced these and many other instances in 

 proof of tlie fact of accleration, Mr. Fisher proceeds to inquire 

 into its cause. That this was not the motion of the vessel, was 



