: The Story of My Life volumes 4-6 by Hare Augustus J C Augustus John Cuthbert - Great Britain History Victoria 1837-1901 Biography; Hare Augustus J. C. (Augustus John Cuthbert) 1834-1903

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samples to follow. They have been published for a great many places all over the country, and single copies can be obtained by sending 10 cents to the Director, United States Geological Survey, Washington, D. C.

Plane tables are almost as easily made as they are bought. If there is no old drawing board around the house, a new bread board from the ten-cent store will serve. For ordinary work, a table which is 15 or 20 in. square will do very well. The board must be mounted on a tripod so that it will be rigid while it is being worked upon and yet can be unclamped and oriented. A brass plate, with a hole in it and a nut soldered over the hole, screwed to the bottom of the board will permit the board and tripod to be bolted together in good shape. Another method, which is not nearly as good, is to drill a hole clear through the board, countersink it on top for a bolt head, and bolt the board and tripod head directly together. With the brass plate and nut, the camera tripod can be pressed into service if a nut of the proper size has been used. The camera tripod is, however, apt to be wabbly with a drawing board on top; a much more satisfactory tripod can be built as shown in the accompanying drawings. Each leg is made of two strips of wood, 3/4 by 3/8 in. and 3 ft. long. These strips are screwed together at their lower ends, gripping a spike between them which will prevent the legs from slipping on the ground. The tops of the strips are spread apart and screwed to the opposite ends of an oak or maple cleat. This cleat is, in turn, screwed to the under side of the circular tripod head.

In place of the two needles and the ruler described for marking the line of sight, most plane-table men use an alidade, which is a combination of two sights and a straightedge. A very simple alidade may be made by mounting two needles on a ruler. The straight edge of the ruler is placed against the needle which marks the station at which the plane table is set up. Then, by swinging the ruler around this needle until its two sighting needles come in line with some object, the line of sight can be drawn directly on the paper along the edge of the ruler. A surveyor in India once made an alidade out of a piece of straightedge and two sights made of native coins hammered out by a native blacksmith. Two pieces of cigar box, one with a fine vertical saw slit in it, and the other with a vertical slot and a piece of fine wire or silk thread stretched down the center, glued to a well planed, straight, flat piece of wood, make a fine alidade. A careful worker may be able to put his sights on hinges so that they will fold down when not in use.

More than anything else, map making rewards care and accuracy, and shows up slipshod workmanship. If the pencils are sharp, the lines fine, and if the work is checked often, beautiful maps can be made with very simple apparatus.

White marks on waxed surfaces may be removed by rubbing lightly with a soft rag moistened in alcohol, after which rub with raw linseed oil.

Machine for Sketching Pictures

An ordinary drawing board, with the attachments shown, provides an easy way to sketch pictures, even if one is not proficient in this line of work. It is only necessary to look through the sight and move the pencil about so that the knot in the thread follows the outline of the landscape or object being drawn.

The size of the machine depends on the one building it, but a fair-sized drawing board is sufficient for the beginner. A strip of wood is fastened to the board, near one edge, which has a metal piece on each end, fastened to the under side and bent up over the end to form an extension for the rod to support the moving parts. The strip of wood should be 3/4 in. wide and 1/4 in. thick, and the sliding arm, holding the pencil, 1/2 in. wide and 1/4 in. thick. A like strip, but much shorter than the one fastened to the board, is also fitted with metal pieces in an inverted position so the projections will be downward. A 3/16-in. rod is run through holes in the metal pieces of the strips at both ends, and soldered to those on the strip fastened to the board. This will make a hinged joint, as well as one that will allow the upper strip to slide horizontally.

A vertical stick is fastened to the front edge of the board by means of a notch and wedge. In the upper end of this stick a very small hole is bored for a sight, similar to a peep sight on a rifle.

To use the machine, set the board on a table, or tripod, and level it up in front of the object to be drawn. Look through the sight at the front of the board and move the pencil about to keep the knot of the thread on the outlines of the picture to be drawn.--Contributed by Wm. C. Coppess, Union City, Ind.

A walnut filler is made of 3 lb. burnt Turkey umber, 1 lb. of burnt Italian sienna, both ground in oil, then mixed to a paste with 1 qt. of turpentine and 1 pt. of japan drier.

Camera surveying is simply plane-table surveying in which the landscape has been photographically picked up and carried indoors. It has the enormous advantage that one can obtain a record of the utmost fidelity in a small fraction of the time taken to do the field work of even a sketchy plane-table survey, and that plotting can be done in the comfort and with the conveniences of a drafting room. When the hours one can work are short or the periods of clear, dry weather are few and far between, a camera is an ideal surveying instrument. It sees and records with the click of the shutter.

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