150 Analyses of Books. [Feb. 



all the usual corrections. Mr. Pond's observations pointed out 

 no such deviations. The deviations that 1 had found agreed 

 with the effects of parallax. The observations that 1 have since 

 made, far more numerous than the former, concur in exhibiting 

 the same results : in showing deviations in certain stars that can 

 be explained by parallax. Every other suggested solution of 

 the difficulty appears quite inadequate thereto. It is, I think, 

 nearly demonstrated, that no change of figure in the instrument 

 has occasioned it, and that the uncertainties of the changes of 

 refraction can have had only a very small share, if any, in pro- 

 ducing the effect observed." 



XXV. On the Effects 'produced in the Rates of Chronometers 

 bu the Proximity of Masses of Iron. By Peter Barlow, Esq. of 

 the Royal Military Academy. (Communicated by John Barrow, 

 Esq. FRS.) 



Mr. Fisher, who accompanied Capt. Buchan in 1818 to the 

 Arctic Regions, has shown, in a paper printed in the Philoso- 

 phical Transactions for 1820, that the rates of chronometers differ 

 on shore and on board, losing in the former situation, but gain- 

 ing in the latter : this variation he ascribed to the influence of 

 the ship's iron on the balance, and his communication contains a 

 detail of the various experiments which he performed, to show 

 that the magnetic influence tends to accelerate the motion of 

 the time-keepers by its influence on the steel part of their 

 balances. Referring to Mr. Fisher's experiments, Mr. Barlow 

 found that five out of the six chronometers which he used were 

 retarded, while all Mr. Fisher's were accelerated. 



From a number of experiments which have been made, Mr. 

 Barlow says, it appears " that a chronometer ought to be kept 

 as carefully at a distance from any partial mass of iron, as the 

 compass itself." 



XXVI. On the Peculiarities that distinguish the Manatee of 

 the West Indies from the Dugomr of the East Indian Seas. By 

 Sir Everard Home, Bart. VPHS^ 



XX Vn. Ofi a neio Compound of Chlorine and Carbon. By 

 Richard Phillips, FRSE. FLS. MGS. &c. and Michael Faraday, 

 Chemical Assistant in the Royal Institution. (Communicated 

 by Sir Humphry Davy, Bart. PRS.) 



We have already given some account of this paper in the 

 A)inals. 



XXVIII. On the Nerves; giving an Account of some Experi- 

 ments on their Structure and FunctionSy which lead to a new 

 Arrangement of the System. By Charles Bell, Esq. (Commu- 

 nicated by Sir Humphry Davy, Bart. PRS.) 



XXIX. Further Researches on the Magnetic Phmiomena pro- 

 duced by Electricity ; with some new Experiments on the Proper- 

 ties of Electrified Bodies in their Relations to conducting Powers 

 and Temperature. By Sir Humphry Davy, Bart. PHS. 



This paper was printed entire in the last number of the 

 Annals, 



