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EQUIPMENT OF THE SURVEYOR.
The reason why I recommend them to be 6 ft. 7.20 in. long is that they are none the worse for being a little longer (some surveyors have their rods only 5 ft. long), and in the absence of an offset staff they may be used for all such purposes.
Bundle of Laths.-I always instruct my men to provide a bundle of laths, as not only are they light in bulk, but are cheap and plenty," and have the advantage (if judiciously selected) of being fairly straight, easily sharpened to a point, and your chainman will not object to carry a dozen or so about with him. For ranging out a long base or other line, especially over very uneven ground, they are simply invaluable. Being white, they can be seen at a great distance, and when done with, if left on the ground, it is not a very serious loss.
Whites. These are very necessary adjuncts to a survey. Varying from 15 in. to 3 ft. in length, they are simply thin sticks cut from a wood or hedge, as straight as possible, pointed at one end and having a cleft cut in the other for the purpose of inserting pieces of white paper. These are very useful in ranging out lines or for establishing stations.
Equipment of a Surveyor.-I do not know whether it is at all necessary that I should offer any suggestions as to the personal habillement of a surveyor, for my own experience has been that I have found the oldest clothes (sound, of course) the most suitable, as it leaves one enjoyably indifferent to the accidents that frequently happen to one's garments. Climbing over fences and walls, crawling through hedges, ascending trees, or fording a stream are not constituted to improve one's clothes if they are required for further use.
I may say, however, that, presuming it to be absolutely necessary to provide an outfit for surveying, the following may be a useful guide. First and foremost, good, strong, and unquestionably watertight boots, with plenty of hob-nails, are imperative, for, apart from risk to health, wet feet for a greater part of the day, especially in winter, do not conduce to comfort or improve the temper. Hightop boots are a great mistake, for not only do they impede the free action of the feet and are clumsy, especially in heavy land, but if one has to work in water, the act of stooping to obtain a better sight of an object may defeat the original intention of keeping the legs and feet protected from wet. Leggings are also a mistake, as they may keep the external wet out, but they also keep the perspiration in. Woollen cord trousers with leather gaiters are the most suitable for any field work. A jacket of good pilot cloth with plenty of pockets is better than anything, for it will stand many hours' exposure to wet. On no account do I recommend the use of a mackintosh, as it is always in the way if not wanted for wear, and
is constantly being torn; and I maintain that, except for driving, the mackintosh is anything but desirable. I will conclude my personal remarks by advising the use of a soft felt or cloth cap with as little brim as possible, as hat-brims are found, especially in instrumental observations, to be not only a nuisance, but often dangerous.
Field Book. The surveyor should be provided with a good fieldbook, for which stout blue paper is generally the best. Some surveyors prefer an oblong book about 8 in. by 4 in., ruled with two lines down the middle forming a central column, on either side of which may be made sketches of fences, buildings, or other objects right and left of the chain-line; but I prefer a quarto book about 7 in. by 6 in., of which I shall have more to say presently. It is advisable to carry several spare pencils (F) in the pocket in case the one being used is lost; but to guard against such a contingency it is useful to tie a piece of string at the end (taking care to cut a notch round the head), and fasten it to the button-hole of your coat, with a sufficient length of string to enable you to manipulate the pencil. The same advice applies to a small piece of india-rubber, which it is always necessary to have. A good clasp pocket-knife is indispensable, not only for sharpening the pencil, but is very useful for cutting sticks, &c. I strongly recommend the young surveyor to carry a pair of good field-glasses, slung by a strap over his shoulder, as he will find them exceedingly useful, indeed on a large survey absolutely necessary. In the absence of a prismatic compass (to which, of course, preference is given) it is desirable to have a pocket-compass, to determine the bearings of points of the survey. It is quite as well to carry a scale, 6 in. long, of say two chains to an inch; a pair of pocketcompasses, a plentiful supply of white paper, string, a few nails, a lump of chalk, and last, but not least, a fairly-sized plumb-bob. I may also say that I have found a pocket-whistle exceedingly useful to attract the attention of my men when beyond the range of one's voice.
I have thus endeavoured to enumerate some of the chief accessories of a surveyor, all of which I maintain are essential for the due and satisfactory accomplishment of his work, especially as he may be, and often is, miles away from any place where such desiderata can be obtained. Remembering this, the student will not think my directions and suggestions too minute or trivial.
BEFORE proceeding to describe the modus operandi of surveying in the field, I wish to offer a few remarks upon the important question of reconnoitre.
Reconnoitre.—It is absolutely essential that the surveyor should, as a first step, make himself thoroughly conversant with the surroundings of the ground he has to survey, by walking all over the estate, whereby he not only gains an intimate knowledge of the various boundaries, the position of buildings, streams, &c., but is enabled to form an accurate idea of the best routes for his principal lines. It has, indeed, been argued that such a proceeding is unnecessary, occupying as it does valuable time; but the question is whether it is not an absolute saving of time to lay out the work so systematically, that, when chaining operations commence, there is likely to be no hitch or delay, by reason of encountering obstacles not previously observed which involve extra work or, possibly, the abandonment of an important line in consequence. One thing is surely important, and that is, to establish the principal stations, which can only be done after a careful examination of the ground.
Sketch Map.-In making a reconnaissance of a proposed survey, it is desirable to make a neat sketch of all the chief features, so that, having determined the routes of your base and other lines, you may delineate them upon this sketch and number them consecutively, which will be found to be of the greatest assistance, not only in subsequent field operations, but in plotting the survey.
Stations. To make a survey of even a simple field, equally with an extensive estate, it is necessary to establish stations at those points to which it may be desirable to run lines. Thus A B C and D (Fig. 4) represent stations which comprehend a complete investiture of this figure, whereby lines from A to B, в to c, c to D, and D to A will be necessary to enable the boundaries of the field to be taken.
Main Stations.-Stations are of a twofold character, main and subsidiary. Main stations represent those chief points which,
whether the figure to be surveyed be regular or irregular, embrace such lines as will command the boundaries of the survey. These stations are shown in various ways, according to circumstances. If the survey is of only a temporary character (such as can be executed in a single day) then poles or ranging-rods may be fixed for the purpose, but if required for an extensive survey, then stout pegs should be driven into
Fig. 6.-Station Mark.
the ground, whilst in some cases special posts, built
any local carpenter
Fig. 8.-Station Marks.
Temporary stations (required the same day) may be established by
Subsidiary Stations.-Subsidiary stations have reference to those points upon the base or other main survey lines, where it is necessary to run auxiliary lines, to pick up the boundaries of internal fences, &c., and are determined according to circumstances, as the process of chaining the main lines is carried on. If in
TESTING THE CHAIN.
the case of an ordinary field (Fig. 9), when after chaining A B and B C, we proceed to take up c D, it will be necessary at e to have a station, and similarly on line D E to do the same at d, for the purpose of measuring the "tie' or "check" line de. Anticipating my remarks upon the field-book, each station should be marked round with a circle or oval.
Testing the Chain.-Before commencing chaining, the surveyor should satisfy himself as to the accuracy of his chain, as, it if has been used before, either from constant pulling through fences, or other causes, it may become elongated, or, in going over rough ground, by treading upon some of the links they may become bent, and consequently shortened, the accompanying as in sketch.
-1 LINK---1-LINK---- LINK--
Test Gauge.-To form a test gauge upon an even surface, preferably a pavement, it is desirable to measure accurately with a rod (the larger the rod the better) 33 ft. and 66 ft. in the same lines. These lengths should be tested by measurement from the other end, and having been determined, marks should be cut in the pavement with a hammer and chisel at each end and in the centre. In the absence of pavement, upon level ground drive in stout pegs, 66 ft. and 33 ft. apart, and having accurately gauged the two lengths, drive nails into the pegs to mark the exact points. A test gauge should be established in close proximity to every
surveyor's office for constant comparison; but in a large survey it is desirable to make one close to the scene of operations, so that each day before commencing work the chain may be applied, and if longer may be adjusted by removing one or more of
K-1 LINK-1 LINK----1 LINK-DOG366
-1 CHAIN or 66 FEET
-1 CHAIN or 66 FEET