Applying the logarithmic formula we have:
As before remarked, the Goldschmid Aneroid requires that both the temperature of the air and of the instrument be carefully taken. Two examples of altitudes taken with the instrument previously referred to (No. 3187) will serve to show the kind of correction necessary, and as both examples apply to the same mountain (Kiarsarge of Conway, N. H.,) they will together indicate the character of the instrument
Ex. I.—July 9th, 1881.
| Station. | Time | Bar. Reading. | Temp. | Correct’ns | Corrected Reading. | ||
|---|---|---|---|---|---|---|---|
| Air. | Inst. | Temp. | Press. | ||||
| Freyb’g. | 6.00 a.m. | 29.51 | 66° | 66° | +.04 | -.10 | 29.65 |
| Mt. Kiarsarge. | 1.00 p.m. | 26.75 | 74° | 74° | +.06 | -.03 | 26.78 |
Ex. II.—August 9th, 1881.
| Station. | Time | Bar. Reading. | Temp. | Correct’ns | Corrected Reading. | ||
|---|---|---|---|---|---|---|---|
| Air. | Inst. | Temp. | Press. | ||||
| Freyb’g. | 7.00 a.m. | 29.34 | 60° | 65° | +.03 | +.09 | 29.46 |
| Mt. Kiarsarge. | 1.20 p.m. | 26.48 | 65° | 75° | +.06 | -.03 | 26.51 |
In both these examples another reading would have been taken at Fryeburg on the return, if the better alternative of securing hourly readings of a stationary barometer at Fryeburg had not been followed. On July 9th there was no change in the Fryeburg barometer. On August 9th the following readings were taken at Fryeburg:
| 7 | A.M. | 29.53 |
| 8 | ” | 29.52 |
| 10 | ” | 29.515 |
| 12 | ” | 29.46 |
| 1 | P.M. | 29.46 |
| 2 | ” | 29.455 |
| 3 | ” | 29.40 |