12. Many surveyors enter their notes in a book about four inches and a half in breadth, and fourteen or fifteen in length when opened; and others prefer a book about eight or nine inches long, and seven or eight inches broad when opened. (See the description of the Field-Book, Part II.; and also the engraven Field-Book belonging to Plates VIII., X., and XII.)

METHOD II.

Measure a main-line as nearly to one of the out-boundaries of the estate as the curves in the hedges will permit ; noting the crossings of fences, and taking offsets as before directed.

At a convenient distance measure another main-line parallel, or nearly parallel, to the first line, so that a number of fences running in that direction may be obtained; and from any two stations in the first line measure lines to some station in the second main-line, thus forming a triangle; so will a station in the second main-line become determined or fixed.

From the first main-line to the second, or from the second to the first, measure lines in order to obtain all the fences which run in that direction. The remainder of the fences of the enclosures contained between the first and second main-lines being obtained by running lines in the most convenient manner, you will have completed the dimensions of a portion of the estate, which may then be laid down.

Parallel or nearly parallel to the second main-line, and at a proper distance from it, measure a third; and proceed with the internal lines as before, and you will obtain the dimensions of another portion of the estate, which may also be laid down.

Carry on the survey in a similar manner, until you finish it.

NOTE 1. This method is illustrated by Plate IV. The field-notes are not given; but the following particulars exhibit the directions of all the lines: The first mainline leads from +1 to + 6; the second from + 6 to +7; and the third line, or second main-line, from +7 to +16. The fourth line extends from +16 to +1; the fifth or tie-line from 16 to + 2; the sixth from +2 to +14; the seventh from +17 to +18; the eighth from+12, through+18 to+3; the ninth from +4 to +10; and the tenth line leads from +8 to +5; thus all the fences between the first and second main-lines are obtained.

The eleventh line, or third main-line, leads from +19 to +29; the twelfth from +29 to +16; the thirteenth from + 29 to +15; the fourteenth from + 15 to +28; the fifteenth from +26 to +13; the sixteenth from +12 to +25; the seventeenth from+23 to +11; the eighteenth from +30 to +31; the nineteenth from +9 through+31 to +22; and the twentieth from +7 to +19, which completes the survey between the second and third main-lines.

The twenty-first line, or fourth main-line, extends from +32 to +40; the twenty second from +40 to + 29; the twenty-third from +40 to +28; the twenty-fourth from +28 to +38; the twenty-fifth from +37 to +27; the twenty-sixth from +24 to +36; the twenty-seventh from +35 to +23; the twenty-eighth from +34 to

+21; the twenty-ninth from +20 to +33; the thirtieth from +32 to +19, which finish the whole estate.

2. In order to practise the learner, a Field-Book may be formed, and the content of the estate found in the same manner as directed in Note 8, Method I.

3. Some writers on surveying instruct their pupils to measure main-lines through the estate to be surveyed; and upon these, by the help of a cross, to erect perpendiculars to the opposite angles and curved fences; and upon these perpendiculars

again, if necessary, to erect other perpendiculars; thus dividing the whole estate into right-angled triangles and trapezoids.

This method is extremely tedious, as many of the perpendiculars will be 12 or 15 chains in length, when the fields are large; and where the fences are much curved, it becomes almost impracticable, in consequence of the great number of offsets that must be taken, in order to obtain a correct plan of the estate.

Besides, when the fence to which perpendiculars must be erected is at a considerable distance from the base-line it will be necessary for an assistant to walk along by the fence, in order to point out to the surveyor the angles and curves to which offsets ought to be taken: and if there be a crooked fence on each side of the base-line, two extra helpers will be necessary, if the surveyor intends to perform his work with expedition. Hence we see that this process of measuring not only subjects the surveyor to a great deal of extra trouble, but also to a very considerable unnecessary expense.

This method I have never followed in measuring estates; neither have I ever seen it followed by any experienced surveyor. But where fields are rectangular the contrary may in such cases be the rule, as shown in the opposite page 165.

METHOD III.

An estate of four sides may frequently be conveniently surveyed as follows: Measure four lines in such a manner that offsets or insets may be taken to the four out-boundaries of the estate; and tie the first and fourth lines together by a diagonal or tie-line measured from one to the other, at the distance of five, six, or more chains from the angular point, according to the extent of the survey; thus you will be enabled to lay down the first four lines, and also the outboundaries of the estate.

Next proceed to obtain the internal fences, by measuring lines in the most convenient manner; some of which must be run from the first to the third, or from the second to the fourth line; or in some other proper direction, so that they may become proofs and fast-lines, into which other lines may be run with propriety.

In thus proceeding, it is evident that a great deal will always depend upon the dexterity and ingenuity of the surveyor, as no directions can be given that will suit every particular case to be met with in practice.

NOTE. This method of surveying an estate is exemplified by Plate XII., the field-notes of which are contained in the engraven Field-Book given with this work.

METHOD IV.

The method which I here intend to describe, is a compound of all the foregoing methods of surveying with the chain; for as there are never two estates to be met with which are exactly alike, sometimes one method claims the preference, and sometimes another;

but a skilful surveyor will always adopt that by which he can take his dimensions and proofs with the greatest accuracy by the fewest lines.

If an estate be in the form of an irregular polygon of five, six, or more sides, and the fences very crooked, such an estate may generally be most easily surveyed by dividing it into triangles, as in Method I.; but if many of the fences of the different enclosures run a considerable way in the same direction, and the fields in general pretty neat trapeziums, it is commonly more eligible to proceed as directed in Method II.

Sometimes an estate varies so much in its shape, that all the methods before described may be used with propriety and advantage; and it frequently happens that an ingenious surveyor adopts methods in particular cases entirely new to himself; care, however, must always be taken to make one line depend upon another throughout the whole survey, so that, when you come to lay it down, you may find no lines whose positions are undetermined.

NOTE 1. Whatever method of surveying is adopted, the field-notes must be entered in a similar manner to those given in the engraven Field-Book. Some surveyors place the letter S against straight fences in the Field-Book, to distinguish them from those that are crooked; but they may be very well denoted by drawing straight or crooked lines, as the case requires.

2. The estates given in this work as examples are not very extensive, in consequence of the serious expense that attends large plates, and the great inconvenience of folding them in books; but it may be remarked that the foregoing methods of surveying are applicable to estates of all sizes, even to those of many thousand

acres.

MISCELLANEOUS INSTRUCTIONS.

1. When you have an estate to survey, never begin your work too hastily. Walk over the estate, examine it minutely, and observe by which of the foregoing methods it can be most easily measured. Next determine upon that point at which it will be most convenient to begin, and never omit to take the range of the first line with a compass. If you do, it will be impossible for you to lay it down in its true position upon the plan.

2. In measuring your main or any other chain-line, put down stations at every place to which you apprehend it may be necessary to run lines in order to complete the survey.

3. You may sometimes put down a station, whether you see any particular use for it or not; because it may become serviceable in correcting an error should one be committed; and if it be not used, it will be immaterial.

4. In measuring your internal lines, it will give you the least trouble to run them from one station to another, if you can make it convenient; if not, you must run them from, and continue them to some chain-line, and measure the distance upon that line to the nearest station, which may be entered in the Field-Book thus: run upon the first line, 30 links S. of + 1, &c.

5. The place where you run upon or cross a chain-line, may be easily ascertained by setting up poles at two of the nearest stations in that line; the crossing will be at the place where you are in a direct line with these poles, which may be represented by marks cut in the ground, pointing out the directions of the lines.

6. In ranging the poles, there must be one fixed at the station from which you intend to depart, and another at the place toward which you direct your line, if there be no natural mark, as a tree, the corner of a house, &c. Then, in a straight line with these marks, put down poles at the distance of 4, 6, or 10 chains from each other, according as impediments may render them necessary.

7. When you are measuring a line across a valley, you must proceed forward until you are likely to lose sight of the station to which you are going; then, let your assistant take a pole to the other side of the valley, and direct him to place it exactly in the line which you are measuring, so as to be seen from the bottom of the valley; to this you may continue your line, and thence to the end.

8. When the stations between which you wish to run a line are so far distant that you cannot see from one of them to the other, or when your view is obstructed by an elevation between them, you must then, accompanied by your assistant, go to the place whence you can distinctly see both; and turning face to face, at a little distance, direct each other to the right or left, until you are both in a right line with the stations; then, one of you putting down a pole, the line will be correctly found. If the line, however, be so long that you cannot possibly find it by the above methods, it must be ranged at random; but, in this case, you should be extremely careful that your pole-ranger keeps one pole in a direct line with another, which he may accurately effect by always having, at least, two

behind him.

9. In measuring a line which passes over a hill, you must attend to the directions given in Part IV. in the method of measuring Hilly Ground; but you will not always find your lines to meet correctly in surveying mountainous estates.

10. When a river runs through the estate it will be necessary to continue some of your lines across the river, in order to tie the whole survey together.