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Documenting Maritime Folklife: An Introductory Guide

Appendix B.2

TAKING THE LINES OF A SMALL BOAT

The methods used to take the lines of a boat vary according to its size, shape, weight, and location. Take, for example, the case of a small fishing boat used by a fisherman in Eastpoint, Florida. The boat selected for documentation was built in 1981 by Frank "Sonny Boy" Segree for his own use floundering and gill netting in the waters of Apalachicola Bay. The twelve-foot craft is constructed entirely of cypress and is held together with galvanized fastenings. Segree calls the boat a "dinky," and because it is small, light, and quite simple in form, it is an easy craft to document.

The first step in taking the lines of the dinky is to lift it off the ground and place it, bottom-side up, on top of a pair of benches. This is done to make it easier to make the necessary measurements. The boat is then leveled with the use of a carpenter's level. Following this, a plumb bob is used to establish perpendicular lines. One line touches the center of the after-most part of the transom, and the other touches the center of the forward- most part of the stem. Thin stakes are driven securely into the ground to mark the forward perpendicular (FP), and the after perpendicular (AP). Next, a baseline is established by stretching a stout string between the stakes. The string is positioned so that it runs horizontally, directly above the centerline of the boat. Then, a carpenter's square and a line level are used to verify that a right angle has been formed at the point where the string is tied to the stakes. At this stage, the basic reference points for the first series of measurements have been established.

Next, various measuring devices, including a carpenter's square, a six-foot folding rule, and a sixteen-foot tape measure, are used. All measurements are checked, and then immediately recorded in a notebook. The first measurement is of the overall length of the boat. Then, the maximum breadth of the bottom of the boat is measured. This point of maximum breadth is designated as Station 2. Two other stations, Station 1 and Station 3, are then established at points half way between Station 2 and the FP, and half way between Station 2 and the AP, respectively. The breadths of the bottom at Stations 1 and 3, and the transom are then measured. Full breadths at each of the three stations and the transom are divided in half and recorded in the table of offsets under "half breadths."

The next series of measurements correspond to the distance between the center line of the boat and the string, or baseline, at all three stations, the bottom of the stem, and the bottom of the transom. These measurements are taken off and recorded in the table of offsets under "heights above base."


Table of Offsets: For twelve-foot "dinky" by Frank "Sonny Boy" Segree, Eastpoint, Florida. Lines taken off at Eastpoint, Florida by Ormond Loomis and David Talor, November 14, 1986. (Measurements given in feet, inches, and eighths).

              Stem    Station 1   Station 2   Station 3   Transom
1. Sheer      1-7-6   1-4-0       1-2-6       1-3-1       1-4-4
   Bottom     0-6-0   0-3-3       0-1-6       0-2-2       0-4-4

2. Sheer      0-0-4   1-6-0       1-11-4      1-11-4      1-9-3
   Bottom     0-0-4   1-2-7       1-9-5       1-9-2       1-7-2
   Skeg       0-0-0   0-0-0       0-0-0       0-0-6       0-0-6
            

(1) height from base line. (2) half breadths from center line.


Following these measurements, the "profile" (that is, the view from the side) of the stem and stern are recorded. These measurements illustrate the shapes of the stem and stern with reference to FP and baseline, and AP and baseline, respectively. Since the stem and stern of this craft are both straight, these measurements are taken off very easily.

The next series of measurements record the "sheer heights," or the distances between the baseline and the top edge of the hull at each station. Taking these measurements requires some degree of concentration, since it is necessary to insure that imaginary horizontal lines running outboard from the base above the stations are perpendicular to vertical lines at the sheer. These measurements are recorded in the table of offsets under "sheer heights."

The next measurements are of the dimensions of other features of the boat: the outboard face of the transom, the skeg, and the rub rail. The thickness of the planking is measured as well.

At this point, all critical outboard measurements have been taken, and the boat is turned over so that interior measurements can be recorded. Important interior features to measure include: the stem head, including cross-section, and height above the sheer; thwarts; thwart risers; keelson; and chine battens. Finally, photographs, both in black and white and color, are taken of the craft from a variety of angles. Close-up shots are taken of important or unique construction details. Later, using all measurements collected, a lines drawing of the dinky is produced. This drawing graphically represents the essential contours of the hull.

 

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