APPENDIX VII.

Hypsometrical Table of Stations between Victoria Bay and Camaroons Mountains.

M. Mann’s instrument is a B. P. (Fah.) by Negretti and Zambra (no number). At sea-level, before starting, his readings were:—

212° ·4 Temperature 77° (Fah.).

„ ·5

„ ·4

„ ·3

„ ·3

The mean was assumed at 212°·4.

In the evening a series of five readings gave a mean of 212°·3. Temp. 88°·50 (Fah.).

On return to Victoria Bay (Feb. 23rd) five readings gave a mean of 212°·1. Temp. 82°·50 (Fah.).

The medium of M. Mann’s instrument was therefore assumed at 212° + ·3. The observations were corrected accordingly, and have been marked (M).

Mr. Saker had a French aneroid. I, one by Messrs. Cary, Strand, London, an expensive and most carelessly made article, whose hand could not even be screwed round for correction.

My B. P. was the zeometer, a new hypsometric apparatus made by Messrs. Casella, of 23 Hatton Garden, London. It answered tolerably, but, as has appeared, the cup was injured during the descent of the mountain on the 27th Dec. 1861, after which the glass tube was used in the ordinary way. Its observations are marked (B).

The average temperature has been assumed at 78°·5, and the calculations have been made by Mr. George, of the Royal Geographical Society.

Observations.

Date. Station. Observation. Altitude.

1861

Dec. 14 Bosumbo 210°·1 (M). Temp. 71°. Mean of two Obs. 1055 feet.

Dec. 19 Bosumbo 29°·6 Aneroid. Temp. 78°.

Dec. 15 Mapanya 28°·2 Aneroid. Temp. 79°.

Dec. 15 Mapanya 207°·3 (M). Temp. 66°. Morn. 2610 „

Dec. 15 Mapanya 207°·2 (M). Temp. 73°. Even. 2683 „

Dec. 21 Ridge Camp 27°·2 Aneroid. Temp. 68°.

1862

Feb. 1 Fern Gate 204° (B). Temp. 80°. 4535 „

1861

Dec. 23 Black Crater 199° (M). Temp. 63°. 7328 „

Dec. 24 Mann’s Spring 198°·7 (M). Temp. 58°. 7466 „

Dec. 24 Mann’s Spring 199°·2 (M). Temp. 63°. 7221 „

Dec. 25 Mann’s Spring 200° (B). Temp. 65°. 6762 „

1862

Jan. 27 Foot of Mount Helen 198° (B). Temp. 66°. 7932 „

1861

Dec. 24 Top of Mount Helen 195°·7 (M). Mean of five Obs. Temp. 58°·50. 9223 „

Dec. 24 Top of Mount Helen 195°·4 (B). Temp. 57°. 9383 „

Dec. 27 Below Earthwork Crater 24°·15 Aneroid. Not worth calculating.

Dec. 27 Above Earthwork Crater . 23°·850 Aneroid. Ditto.

1862

Jan. 28 Crater of Mount Isabel 193°·9 (M). Mean of five Read. Temp. 50°. 10,187 „

Jan. 28 Summit of Mount Isabel 193°·4 (B). Temp. 60°. 10,590 „

Jan. 28 Camp Saker 193° (B). Temp. 48°. 10,595 „

Jan. 28 Foot of Victoria Mountain 193°·5 (B). Temp. 60°. 10,530 „

Jan. 30 Foot of Mount Hooker 192°·7 (M). Temp. 48°. 10,875 „

Jan. 30 Summit of Mount Hooker 191°·2 (M). Temp. 45°. 11,725 „

Jan. 14 Victoria Crater 188°. Temp. 58° Obs. by Mr. Saker. 13,806 „

Jan. 30 Summit of Victoria Mountain 189°·7 (B). Temp. 51°. 12,696 „

Jan. 29 Summit of Albert Crater 189°·5 (B). Temp. 62°. 12,948 „

Jan. 29 Highest Point of Albert Mountain 189°·2 (B). Temp. 62°. 13,129 „

In assuming 78°·50 (Fah.) as the mean temperature at sea-level, I have been obliged, for want of other comparison, to adopt the mean of M. Mann’s observations.

Before leaving Victoria Bay, he made, between the 6th and 12th of December, 1861, a series of thirteen maximum and minimum observations, whose mean is 79°.

After returning to Victoria Bay, he made five maximum and six minimum observations between the 19th and the 24th February, and their mean is 78°.

My friend Major Noeli, of the Spanish artillery, supplied me at Fernando Po with the following table. It will be seen that the mean of December, January, and February, 1859-60, are also 78°·50 (Fah.).

Observations of Temperature by Major Noeli, H.C.M.’s Army, at Fernando Po, 1859-1860.

Observations taken at 6 a.m., 8 a.m., 10 a.m., noon when possible, 3 p.m., 10 p.m.

Place:—Room facing N.E., and about 100 feet above sea-level.

Date. Thermometer. Barometer. Remarks.

Max. Min. Mean. Mean.

Sep. 1859. 81·0 69·0 75·44 29·66 Only taken during last half month. Twelve days’ heavy rain. Frequent fresh breezes when there was no rain.

Oct. „ 83·5 70·0 76·40 29·65 Nine days’ rain. Sea-breezes when no rain.

Nov. „ 85·0 70·0 78·05 29·61 Sixteen days’ rain (less copious and shorter), chiefly in early morn. Five mild tornados. Frequent breezes.

Dec. „ 86·0 69·0 78·90 29·59 9 A.M. 26th. Tornado and rain. Another rainy day, fine drops. Frequent breezes.

Jan. 1860. 86·5 67·5 77·87 29·59 One rainy day. Frequent breezes. Harmattan. Great heat on calm days.

Feb. „ 88·0 69·0 78·73 29·54 One day’s rain. Various tornados. Sometimes no sea-breeze till 3 P.M. Great heat. Therm. 88° only one day.

Mean of 6 months. 85° 69°·1 77°·56 29·612

At Fernando Po the barometric wave is at its highest at 9·10 a.m. and 9·10 p.m., and at its lowest at 3·4 a.m. and 3·4 p.m.

THE END.

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