122 On the Sea and Land Rates of Chronometers. 
dence in the country, without finding their rates affected by the re- 
moval in any sensible degree—certainly not to any thing like the ex- 
tent which Messrs. A. and D. represent as common. 
After reading the Jetter of Messrs. A. and D., we took four chro- 
nometers, and after ascertaining their rates in "Change Alley, we re- 
moved them to our private residence, about three miles from thence, 
and ascertained their rate of going there. We then brought them 
back to Change Alley, and again found their rates. After this, we 
had them carried around the Royal Exchange in the hand for about 
half an hour every morning, for several days; and after this trial we 
put them in an iron chest for the same period. 
We subjoin the average rates during their various trials, from which 
it will be seen that no systematic variation took place which could be 
attributed to the peculiar circumstances under which the chronome- 
ters were acting. 
Average Rate per Day during each of the Trials. 
Royot Chron:|i neg! |" dence: | dey ceaalt| Beohanen. |) Hania 
ui (i TT i aN 
LON EON 07 1 0 
1978 | =5 0 | =5 3 | =52 |] =5 7 | =5 2 
745 | =50 | =5 1) =5 1 | =5 8 | =5 6 
925 | =16 | =12 | =14 | =15 | =18 
We may further state on this subject, that, in August, 1833, we 
sent two of our chronometers, Nos. 1731, and 1751, to the Royal 
Observatory, Greenwich, on private trial. Their average rates for 
a short time previous were, | 
It Mt 
No. 1731 + 0 8 : 
7a O68 ; per diem. 
After their having been at the Observatory some time, the follow- 
ing were given to us as the rates they had kept there : 
UL 
1731 At Greenwich... + 1 2 1751 At Greenwich... +0 7 
o Change Alley + 0 8 At ’Change Alley + 0 3 
Difference in Rate + 0 4 Difference in Rate + 0 4 
It is evident that these chronometers shew no remarkable change 
of rate, as resulting from their removal from London to Greenwich. , 
With respect to the difference between land and ship rates, on 
which much has been said and written within the last few years, we 
