Vol. XII. No. 303. 



THE AGRICULTURAL NEWS. 



397 



STUDENTS' CORNER. 



INFORMATION CONCERNING LAND 



MEASUREMENT. 



II. 



In the previous article information was given in regard 

 to the measurement of survey lines. In the present article, 

 information will be given in connexion with the laying out 

 of survey lines. 



PRELIMINARY INSI'ECTION. 

 In all chain surveying work the area to be measured is 

 included within an imaginary triangle or a series of imaginary 

 triangles, and the lines forming their sides are measured with 

 the chain in the manner already described. In order to 

 ascertain the best position, and to obtain a clear course as free 

 from obstacles as possible, it is first necessary to walk over 

 and examine the ground. A rough sketch map of the area 

 should be made and the lines it is intended to lay down 

 should be roughly indicated on this preliminary plan. 

 Having done this, the points or stations should be selected 

 in the field, and the poles ranged out and inserted perfectly 

 straight. 



Fio. 32. 

 These poles must be set up exactly perpendicular; and 

 where the lines are of considerable length their fixation 

 may be facilitated by using a field glass, care being taken 

 that the axis of the instrument is in true alignment. 



THE li.^SE LINE. 



In deciding upon the arrangement of the lines, an 

 attempt .should be made as far as possible to include the 

 whole area within one large triangle or a system of large 

 triangles. The base of the triangle, or of the main system 

 of triangles should be extended throughout the whole length 

 of the survey wherever circumstances will allow. This line 

 (or base) is called the 'base line'. It is the first line that is 

 laid out and generally the first line to be measured. 



THE i;UESTION OK OFF-SETS. 



Considerable difficulty is often experienced in regard to 

 the mea.surement of the boundary, particularly if it is very 

 irregular. Fig. 32 shows that part of the boundaryjniay lie 

 within and part without the external survey line. The 

 measurement of the areas cut olf in this way is done by 

 means of taking off-sets, that is to say, by measuring at 

 regular intervals from the outside chain lice perpendicularly 

 to an opposite point on the boundary line. Generally .speak- 

 ing a limit of 20 to 30 links should not be exceeded in taking 

 offsets. To avoid the use of long offsets, great care should 

 be taken to get the outside survey lines of the big triangle 

 to pass as near the objects or boundaries of the area to be 

 surveyed as practicable. 



TIE LINES. 



The skeletons of the survey having been measured, it is 



next necessary to prove their accuracy by means of further 

 measured lines, termed check, or 'tie lines \ and this is best 

 obtained by lines measured from the apex to the base of each 

 triangle. Where lines from the apex awe not available, owing 

 to the nature of the ground, the triangle may be checked by 

 lines measured across the adjacent sides of any two angles. 



The student will more readily understand what has been 

 stated above by referring to Fig. 32 which represents a seven- 

 sided Held such as might be found on any esute or plantation. 

 It may be regarded as being, say, from 15 to 20 acres in area. 

 One of the sides CE is straight and the fence A m. D -' B is 

 too much bent to be taken by one line crossing and recrossing 

 it with off-sets taken to the right and left. EC is the base 

 line and EDC is the main triangle. In the present case 

 III II is the tie line. is one of the offsets. 



EC, AB, BC, CI), DE, and EA will be measured con- 

 secutively. 



The manner of plotting these lines will be dealt with 

 in another issue. 



Dominica Planters' Association.— A general 

 meeting was held in the St. George's Hall on October 27. 

 The members present were Mr. E. A. Agar, Chairman, INfessrs 

 George Carew, Gerald Carew, H. A. Frampton, E. Frampton, 

 A. K. Agar, L. L. Bell, J. F. .Marsden, A. St. Hilaire, 

 A. Davenport, and G. G. Downing, Honorary Secretary. 



The principal busine.ss of the meeting was the revision 

 of the rules, which were considerably altered and improved. 



There was a discussion as to the desirability of inducing 

 the surplus labour from Panama to come to Dominica, but 

 the meeting did not think that they would be of much use 

 now as ordinary agricultural labourers. 



It was also resolved to ask His Honor the Administrator 

 to take steps to check the ever-increasing crime of praedial 

 larceny, as the Produce Protection Ordinance has not done 

 what was hoped from it to protect the thefts of those 

 products detailed in that Act, while no attempt has ever 

 been made for the adequate protection of the growers of 

 ground provisions. 



DEPARTMENT NEWS. 



The Imperial Commissioner of Agriculture left 

 Barbados by the R,:\l S. 'Magdelena' on Jlonday, 

 December I, 191o, tor an official visit to Antigua. Dr.' 

 Watts is expected to leave Antigua by the K.M.s! 

 'Cobequid' on December 14 for St. Vincent, from which 

 island on the 22nd instant, he embarks on the 

 Intercolonial Royal JIail Steamer and is expected to 

 arrive in Barbados on December 24. 



The Board of Trade Journal (October 23, 1913) 

 publishes an article on the oil palm industry in Southern 

 Nigeria in which it is stated that the present insufficient 

 available labour is adversely affecting the palm oil and kernel 

 industry. Southern Nigeria being a new and progressive 

 country the calls on labour are so many and varied that 

 the latter is diverted to the work which attract the 

 labourers most. (See page 398 of this issue.) 



