\ ON THE KEW OBSERVATORY. 81 
Yequired to be done to prevent the entrance of rain (when violent gusts 
- occur) at the cap. 
The Voltaic Electrometers are a little deteriorated (in appearance princi- 
pally). ? 
tie Henley Electrometer (apud Volta) is certainly in a rather less efficient 
state than when new. Friction of pivots is ever bad in electrometers, and 
want of employment increases the evil tendency. 
The Wind Vane has been nearly destroyed by a fall, in consequence 
of some bad soldering at its supporting ring. 
The following instruments are all in an efficient state for use in obser- 
vation :— 

The Galvanometer. Thermometer (standard). 
Discharger. Wet-bulb Hygrometer. 
Gold-leaf Electroscope. Daniel's Hygrometer. 
Distinguisher. Saussure’s Hygrometer. 
Three Night registering Electrometers. Balance Anemometer. 
Barometers (two). Rain and Vapour- Gauge. 
The numerous instruments which have been employed in electric, magnetic, 
and other experiments and extraordinary observations are not materially, if 
_at all deteriorated. They will be carefully enumerated in a general catalogue 
of the actual contents of the Kew Observatory arranged under six heads, 
viz.— 
1. Fixtures, furniture, &c. found in the building on the Ist of August 
1843. 
2. Apparatus supplied by means of a subscription in 1843. 
3. Apparatus, and materials for apparatus, purchased out of sums 
granted annually by the British Association, including a 50/. grant from 
the British Association for experiments. 
4, Apparatus presented to the British Association. 
5. Books the property of the British Association. 
6. Articles which are on loan to the British Association. 
II. ExPperIments, &e. 
Soon after the meeting of the British Association at Swansea in August 
1848, being very anxious to proceed with the magneto-registering system, I 
began to make drawings of apparatus on the plan of suspending the declina- 
tion magnet at right angles (horizontally) with the index arm (all else re- 
_ maining as before), in order to procure a greater extent of scale with the 
_ same amount of light ; but reflecting upon some valuable conversation which 
Thad the honour to hold with Dr. Lloyd at the Swansea meeting, and on some 
_ Suggestions of his afterwards, I made diagrams and calculations for trying his 
_ methods of attaching the lens to the magnet, and deflecting it by separate 
_ Magnets, or by reversion of it, in order to procure a larger range of the in- 
 strument itself. I submitted these ideas, &c. to Colonel Sabine, and received 
_ obliging and very useful hints from him. I also consulted profitably Mr. Ross 
the optician. 
. At the beginning of November I had made arrangements, drawings, &c. 
_ for mounting a magnet on Dr. Lloyd’s plan, which it was intended should be 
_ tried at Woolwich ; but the apartment (or observatory) selected not having 
“ultimately been deemed very well-fitted for the purpose, I thought that the 
~ Kew building and the Kew establishment could and ought to be appropriated 
_ to the attainment of so desirable an end, that it was one exactly calculated 
_ for the proper business of the establishment, and Colonel Sabine agreed in 
these views I believe. : 
; 1849, G 
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