644 
ME. AIET’S ACCOElv'T OF THE COXSTErCTIOX OF 
observations connected with the same subject, but at a higher temperature in a ver%' 
steady season. 
The Royal Astronomical Society’s Standard and Ordnance Bar lA were mounted as 
formerly (lA upon its semicircular pieces), and the Royal Astronomical SocietA’s 
Standard was longer than lA, — 
1844, May 14, from 20 comparisons at temperature 65°-5, by 0-001185 inch. 
Then 2 A was inserted in place of lA, and after waiting some time for steady weather, 
the following comparison was made, giving the Royal Astronomical Society’s Standard 
longer than 2A, — 
1844, June 17, from 20 comparisons at temperatui’e 65°-47, by 0-001222 inch. 
This is the last comparison made by Mr. Baily. 
In the month of April Mr. Baily was occupied with comparisons intended to verify 
the invariability or variability of the Royal Astronomical Society’s Standard. They con- 
sisted, partly of comparisons of the middle 3 feet of that scale with the middle 3 feet 
on other tubular scales, of exactly similar construction, with which it had been com- 
pared in the year 1835 ; and partly of comparisons of different measui-es on the same 
tube, which also had been compared in 1835. 
The Royal Astronomical Society’s scale was found to be shorter than Mr. B.aily’s 
tubular scale No. 6, — 
o inch. 
1844, April 8, from 20 comparisons at temperature 50-67, by 0-000120 
9, from 20 comparisons at temperature 52-61, by 161 
In 1835, the Royal Astronomical Society’s scale was longer than Mr. Baily’s bv 
0-000046 inch. 
Mr. Simms’s tubular scale No. 4, of construction exactly similar, was substituted for 
Mr. Baily’s. The Royal Astronomical Society’s scale was found to be shorter than 
Mr. Simms’s No. 4, — 
o inch. 
1844, April 14, from 20 comparisons at temperature 56-33, by 0-000180 
15, from 20 comparisons at temperature 56-90, by 163 
In 1835, the Royal Astronomical Society’s scale was longer than Mr. Simms’s by 
0-000102 inch. 
Mr. Baily’s scale No. 5 and Mr, Simms’s No. 4 Avere then mounted together, each on 
its own rollers ; and Mr. Baily’s was found to be shorter than Mr. Simms’s, — 
„ inch. 
1844, April 16, from 20 comparisons at temperature 57-11, by 0-000087 
17, from 20 comparisons at temperature 56-76, by 116 
In 1835, Mr, Baily’s was longer than Mr. Simms’s by 0-000042 inch. 
