CO885-(19-20) — Page 430

51

PUBLIC RECORD OFFICE

Reference:

C.O.

the height of the point on the pier above the bamboo was measured and occasionally checked.

The greatest range of tide was found to be 6.05 feet, the lowest 1.87 feet, whilst the daily means had a range of 1.16 feet. The mean value thus obtained for the height of the point on the pier was 5.310 feet above M.S.L.

Levelling. A double line of check-levels was run from the pier to a point of the base-line (Peg 54). Expense being limited, no level was brought out from England, and the best instrument available locally was a 12-inch engineer's level having a diaphragm with fixed stadium points. The latter are inferior to cross- lines, as even with the steadiest motion possible of the levelling-staff, they continu- ally vary their apparent position laterally on the scale of the latter.

The heights of the ends of the base were obtained from the level readings of the base-measurement. Owing to slight discrepancies between the heights of the transferring instrument in settings over ground points, to the shifty nature of much of the ground, and to the pattern of level available, the difference in these heights in two measurements is large. The instrument used in this case was a 10-inch engineer's level of old pattern. The results may be tabulated as follows:-

Ist Measure. 2nd Measure-

*

ment.

Mean.

Add

ment.

Height above M.S.L.

Peg 54 (from pier)

- 0,576

-0.544

8. terminal (from p. 54)

- 0.500

N. terminal (from p. 54)

-- 2.340

- 1.829

-0.386

+ 0.218

2.081 0.069

5.310 4.750 4.750

+ 4.750

+ 2.666 + 4.681

These values, though rough, were considered sufficiently accurate for the pur- poses of this triangulation.

The mean height taken for the base-line was 4 feet, and, assuming that owing to the method of standardisation no addition need be made for the height of the tape above the ground, the correction to be deducted for height above M.S.L. was calculated to be 0.0029 feet.

tion.

NOTES.

Topographical Sketches.-The nature of the country and the climate are much against any topographical sketches being undertaken in addition to the triangula- At the same time, with some additional labour in clearing, which, for the most part, would be done during theodolite work, the topography of the main features of the country could probably be fixed by photographic methods with very

fair accuracy.

The slopes and deep valleys in the immediate neighbourhood of a hill-point are seldom visible, but good views of opposite slopes and prominent features from one to four or five miles away could, with clearing, usually be got. With a little extra labour it might often be possible to occupy a point in a central site on the line of march, whose position could be resected, and, with one or two pairs of photographs, much of the central areas of triangles could thus he filled in without serious delay to the triangulation. Further filling in of gaps could be done later according to requirements, and a general map produced of

fair accuracy.

very

All photographic equipment would have to be specially protected against damp, and plates packed in small quantities in air-tight tins. The extra weight carried is slight.

The advantages of plotting the results in this country are obvious, more especially if hereafter rapid surveys of special areas were required.

Transport. The expense of the present system of labour and difficulties that it involves makes it advisable to obtain some cheaper and more independent means of transport than that of carriers. It is probable that any form of pack-transport, even with mules, which initially cost £60, or with donkeys, which are very slow, would, if feasible, be a saving of time and expense.

This question awaits further experience of the nature of the tracks and difficulties of travelling with animals in the interior.

19266

SIR,

No. 24.

SOUTHERN NIGERIA.

MAJOR E. H. HILLS to COLONIAL OFFICE.

(Received 9 June, 1909.)

[Answered by No. 25.]

32, Princes Gardens, S.W., 9th June, 1909. WITH reference to your letter, No. 11641/1909, of the 8th April last,* relative to the inspection of the Survey Department of Southern Nigeria, I have the honour to forward herewith my report.

2. As you will observe, I have been driven to the conviction that Mr. Cotton is quite incompetent as a Director of Surveys. I do not think that anyone making

the most cursory inspection of the work carried out under his superintendence could possibly form any other opinion.

3. For some of the figures and facts in my report I am

to particulars obtained from Mr. Cotton.

necessity indebted in his statements that it is dangerous to place much reliance upon information I have, however, found him so inaccurate given by him, and, where possible, I have applied independent checks. however, my report be seen by him he will doubtless contend that facts are wrongly Should, stated and that my deductions are thereby vitiated. In order to anticipate this objection, I should like to express my confidence that, while I may possibly be in error on some minor points, my main conclusions are incontestable.

4. A summary of this report was handed to His Excellency the Acting Governor before I left Lagos.

5. I arrived at Lagos on May 3rd, and left on May 23rd, reaching Plymouth on June 8th.

My period of absence, and hence of employment under the Colonial Office, was therefore April 17th to June 8th, inclusive.

Enclosure in No. 24.

I have, &c.,

E. H. HILLS.

REPORT ON THE SURVEY DEPARTMENT OF SOUTHERN NIGERIA.

History.

The past history of survey work in the Protectorate

given in sufficient detail

in the annual reports of the Colonial Survey Committee, and need not be recapitu- lated here.

Staff.

The staff of the Department, as authorised in the Estimates for the current year, is as follows:-

Director at

Deputy Director at

6 European Surveyors at an average of

6 Native Surveyors at an average of

European Draftsman

12 Native Clerks and Draftsmen

3 Learners.

Messengers and Labourers.

£800

600

386

126

350

Owing to the large amount of sickness and the necessarily liberal leave regula- tions, the numbers at work at any given time will always be substantially short of the above total. Thus, at the present date (May, 1909) the actual working strength

is :-

Director.

Deputy Director.

4 European Surveyors.

26548

• Not printed.

D 2

885

20 PUBLIC RECORD OFFICE, LONDON

ALLY WITHOUT PERMISSION OF THE BE REPRODUCED PHOTOGRAPHIC- COPYRIGHT PHOTOGRAPH-NOT TO

52