ON THERMOMETRIC OBSERVATIONS IN THE ALPS. 
nine Minimum Thermometers. 
369 
Lowest 
Temp. (By whom observed. Date ir Bias Remarks. 
recorded. as 
C. 
—14°-8 | W. Mathews, Jun.) 1859. Aug. 29. | 1861, July 19, F. F. Tuckett, “Spirit separated.” 
Sept., F. W. Jacomb, ditto. 
_ -17° T. Blandford. 1860. Aug. 30. | 1861, Aug. 10, Dr. Kolbs, ‘Spirit disappeared, no 
No obs. flow visible; index on bottom of bulb.” 
—25° H. Lawrence. 1861. Aug. 25. | Touched, and possibly disturbed by guide. 
—10° T. Blandford. 1861. Aug. 7. | Reset on 5th by Rev. L. Stephen. Aug. 23, 1861, 
No obs. H. Lawrence, “ No index visible.” 
, ” 
” 
” 
” 
7° W. Mathews, Jun.) 1859. Aug. 29. 
—35°? |S. Winkworth. 1861. June 22. | ‘ Minimum —41°. Spirit separated from +21°°5 to 
+32°°5.” Result doubtful. 
No obs eee see wee =| 1862, July 4, F. F. Tuckett, “Cairn partly buried in 
snow ; could not find therm.” 
y tee tee eee 1862, July 4, F. F. Tuckett, “Securely deposited in 
upper part of cairn.”’ 
” oo eos 1861, Sept., F. W. Jacomb, “ Not to be found; pro- 
bably stolen.” 
” . 
wy J. K. Stone. 1860. Aug. ‘“ Spirit separated.” 
” 
} —9° Rey. C. H. Pilking- | 1861. Aug. 17 | ‘Spirit separated from 10°°5 to 11°-5, and from 36°°5 
ton. to 39°.” 1860, Sept. 14, R, B. Shaw, —8°5, 
No obs. 
—21° A. P. Whately. 1861. Aug. 19. | “In good order, and agreed with Mr. W.’s thermo- 
No obs. meter.’”’—1861, June 25, F. F. Tuckett, “ Not to 
7 be found ; probably covered with snow.” 
—1"7 F. J. A. Hort. 1860. Sept. 5. | “ Stood 0°°5 C. lower than a mercurial thermometer 
by Mr. Casella.” 
|—27°, 1861) M. Carrel 1861. June 27. | 1860, Aug. 8, G. H. Strutt, —7°. 1861, Aug. 9, 
|—23°, 1862 i * 1862. June. F. W. Jacomb, —7°. 
No. obs 
—9° T. Webster. 1860. Sept. 9. | 1861, July 4, W. G. Fry, “Could not find thermo- 
meter, and believed it had been broken.” 
—12°5 | T. Blandford. 1861. Aug. 6. | 1860, Aug. 18, Rev. L. Stephen, —3°. 
pels W. Mathews, Jun.| 1859. Aug. 29. | ‘‘ Index close to bulb, and evidently not properly set 
No obs when deposited by Balmat.” 
—2° F. J. A. Hort. 1860. Sept. 27.| 1861, July 5, 31° (?) De la Fontaine. 
re Messrs. Green and| 1862. May 28. 
5-10 5{ Smallpiece. | 1862. Sept. 24, } In good order. 
Among the instruments provided for the purpose by Mr. Casella, the 
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| tion. 
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writer has found that a slight difference in the size of the bulb has a very 
marked difference in the indications of the instrument, amounting in some 
cases to 2°°5 C. 
It was also found that the interval of three minutes allowed for the ex- 
posure of the black-bulb thermometer to the sun was too great. At con- 
siderable heights the air does not often remain perfectly calm, nor the sky 
completely clear of passing films of cloud, for many minutes together. It is 
necessary to allow an interval long enough to make an error of, say, one 
second in the moment of reading the instrument not very sensible in the 
observation ; but one minute is certainly preferable to three ; and after experi- 
