been materially improved; the fences and other objects in the survey being sketched therein, on the right and left of the chain line. The author has here departed from the original form by numbering the lines, as being more convenient for reference in large surveys than the method of numbering the stations or marking them with the letters of the alphabet, as recommended by Mr. Rodham.

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Sta

In the plan referred to, the first line, No. 1, commences at a station in the turnpike road, near N. W. wing wall of the bridge crossing the river Ouse, and is ranged in a northwesterly direction, and so as just to avoid the wood, No. 1; the numbers of this and the other lines being placed in small circles on the lines, to prevent their being mistaken for the numbers of the fields and other enclosures, the same numbers being also placed on the left of the station lines in the field book. tions are left in line 1 at 250, 1260, 1890, 2335, 2875, 3720, and 4700 links for secondary lines on the right and left of it: this line, having crossed seven fences as shewn in the field book, terminates, in the northern boundary fence of the estate at 4726 links: it will also be seen that the direction of the straight fence on the south of the orchard and homestead, No. 11 is taken, on the left of this line, at 1424 links. The stations referred to, which are afterwards used in the survey, are put down on the right of the station line in the field book, opposite their respective distances; although they might with equal propriety be put immediately above their respective distances in the station line. Some surveyors prefer this latter method, as the stations do not thus interfere with the space allotted to the offsets on the right of the line: the student is, therefore, at liberty to adopt which method he chooses.

Line 2 commences outside the north-western angle of the estate, crosses the boundary at 24, runs through the station at 4700 in line 1, and terminates at the eastern fence of the turnpike road, stations being left therein at 2360 and 3184, and offsets taken therefrom to the northern boundary fence of the estate, which fence is sketched in the field book.

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Line 3 begins from at 3184 in line 2, turning to the right thereof. This beginning of line 3 is thus marked in the field 5ook:-"from at 3184 Г ," the symbol denoting that line 3 turns to the right of line 2, the symbol being used when the line turns to the left. This line runs near the turnpike road, for a considerable distance, the two fences of which are taken therefrom by double offsets, as shewn in the field book; and, after crossing the occupation-road between fields 8 and 9, meets the

at 1260 in line 1, the direction of the straight fence between fields 4 and 8 being taken by a short tie line, as shewn in Prob. IX., Chap. III. The length of this line is 3074 links, and with lines 1 and 2 constitutes a triangle, which may be laid down in the usual way: thus,

Line 4 starts from O at 250 in line 1, and closes on at 2097 in line 3, taking the turnpike road by double offsets.

Line 5 starts from O at 1420 in line 3 and meets at 2360 in line 2, taking the western fence of field 3 by offsets.

Line 6 and 7 complete the survey or filling up, as it is usually called, on the north-eastern side of line 1. It is here proper to observe that the four last lines must all fit, or very nearly so, between their proper stations, when laid down on the plan; otherwise some error or errors have been made, either in the measurements, or in the entries in the field book, or in laying down the lines, which must be corrected before the work proceeds any further.

The next main line 8, starts from the beginning of line 2 Г of which proper notes are made in the field book, and ends on the north bank of the river Ouse, near the south-west corner of the estate, taking the western boundary thereof by means of offsets throughout its whole length, as shewn by the field book. Line 9 starts from at 4713 in line 8 and meets Oat 459 beyond at 250 in line 1, the distance between these stations being measured on finishing line 9, as it was not foreseen that a O was required for this line, when line 1 was measured, the entry being made as shewn in the field book.

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The remainder of the field book is here put down without sketching the fences, &c., which the student can readily do himself for practice from the plan.