Fig. 27. S-bottom hull (A), compared to a hard (B) and soft (C) chine hull

The oldest type of engineered boats is dugout canoes, which were built by hollowing out a log. These designs generally had rounded bottoms, which made best use of the round shape of the logs. Traditional planked hulls in most cultures are built by placing wooden planks oriented parallel to the waterflow and attached to bent wooden frames. This also produced a rounded hull, generally with a sharp bottom edge to form the keel. Planked boats were built in this manner for most of history.

The first hulls to start incorporating hard chines were probably shallow draft cargo carrying vessels used on rivers and in canals. The barge and later the scow used a flat bottom and near vertical sides, which provided the maximum cargo carrying capacity (in both space and displacement) available for a given depth of water.

The scow in particular, in the form of the scow schooner, was the first significant example of a hard chine sailing vessel. While the squared off scow hulls were ugly to sailors accustomed to the sleek, rounded hulls of the time, a scow could carry far more cargo, and while a laden scow was slow and difficult to sail, when not heavily laden it would keep up with the traditional schooners sailing to windward. While sailing scows had a poor safety reputation that was due more to their typical cheap construction and tendency to founder in storms. As long as it sailed in the protected inland and coastal waters it was designed to operate in, however, the sailing scow was an efficient and cost effective solution to transporting goods from inland sources to the coast.

II. Master the Active Vocabulary:

angle – угол

bottom – дно, днище

to indicate – показывать, указывать

chine – острая скула (место соединения днища и боковых стенок судна)

plywood hull – фанерный корпус

dugout canoe – узкая лодка, выдолбленная из бревна

a log – бревно

to attach – присоединять

scow – баржа

significant – значительный

windward – наветренный

steamboat – пароход

punt – плоскодонный ялик

hollow out – опустошать

III. Answer the following questions:

1. What does the term hard chine indicate?

2. How is a method of building hard chine boat hulls called?

3. What is the oldest type of engineered boats?

4. How are traditional planked hulls built?

5. Is the scow the first significant example of a hard chine sailing vessel?

6. Can you describe the punt?

IV. Read and translate the text: “Plank hulls”

The limitations of wood plank construction, the desire to maximize cargo volume, and the quest for fast, easy hull building led to a new type of construction method unique to chined hulls. This new method used wooden supports placed along the chines called chine logs to provide strength where the chines joined. Beams are then attached to the chine log to support planks running parallel to the chine, while cross-planked sections such as a typical scow bottom may be attached directly to the chine log. This method of construction originated with the sailing scow and continues to be used today, primarily in home built boats. Use of a chine log provides some structural support, but most chine log hulls are primarily monocoque in nature, with the hull planking itself bearing most of the structural load.

Chine log construction works best for hulls where the sides join a flat bottom at a right angle, but it can be used for other angles as well with an appropriately angled chine log. Builders of small boats such as punts, where the plank thickness is relatively large compared to the size of the hull, can dispense with the chine log and nail intersecting planks directly into one another.

V. Ask as many questions as possible:

1. Chine log construction is a method of building hard chine boat hulls.

2. The oldest type of engineered boats is dugout canoes, which were built by hollowing out a log.

3. Punts are generally used for recreation and are popular with duck hunters for their ability to move about in marshy hunting areas.

4. The scow was the first significant example of a hard chine sailing vessel.

5. A chined hull built out of plywood will often be designed to keep most of the joints between the plywood sheets at the chines, thus making the building process easier.

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