Agronomical Obfervations. 175 
take that trouble, I fiiall be much obliged to you if you 
will let me know the refult. 
The account I fent you of the going of one of my 
clocks, I am afraid, is not worth laying before the Royal 
Society, as no conclufion can be deduced from it ; but I 
am certain, that moift weather, for any length of time, 
makes it go flower, probably by increafing the weight of 
the rod : perhaps covering it with tin-foil would prevent 
its imbibing moifture. The other clock, with a maho- 
gany pendulum, does not go well, as the fibres of the 
wood are not ftrait, and it warps from the changes of the 
weather. 
I have taken fome pains to fix the hygrometer to fome 
llandard, but in vain. One I have had about five years, 
though adjufted laft fummer, has almoft loft the power 
of abforbing moifture; fo that its contracting is to its 
lengthening as 1 to 3. 
In 1774 I fent my achromatic telefcope to dollond 
and got another from him much better in every refpedt 
magnifying 150 times, with an achromatic objedt-glafs 
micrometer, and a very firm Hand and polar axis. It has 
but one fet of Aiding tubes at the object end, yet it is 
very fteady, and anfwers perfectly well, when once it is 
fixed to the object. 
Being 
