Research: Topics: Transportation: Guide to Canal Records

Guide to Canal Records

Glossary of Canal Record Terminology

The following terms are commonly found in series descriptions of records documenting the survey, construction, design, and improvement of New York State canals.

Aqueduct: a conduit or artificial channel for conveying water.

Aqueduct bridge: a structure that carries a canal over a river, stream, or valley.

Berm: a side bank of a canal, also known as the heelpath.

Berm side: the bank of a canal opposite the tow line.

Blueline: a non-reproducible blue image or outline usually printed photographically on paper or plastic sheeting, and used as a guide for drafting, stripping or layout. Sometimes called blind image.

Blue line: a line representing state owned land.

Bolts: a kind of bounds.

Boundary points & pointers: the corners of zone boundaries and the points where two or more zone boundaries join, are established and their locations are recorded.

Bounds: boundary lines; metes and bounds is method of describing land by measure of length (metes) of the boundary lines (bounds).

Culvert: a traverse drain or other conduit channeling water; feed culverts are hollow spaces, or tunnels, within lock walls through which water for filling or "feeding" a lock and for emptying it is conducted.

Dam: a structure built across a watercourse to maintain water levels and confine and keep back flowing water (a fixed dam is a permanent structure without movable parts; a movable dam is one which can be set up or thrown down as desired).

Feeder: diverted stream water used to supply water to maintaining the canal level.

Flowage (flow) line: a contour or line around a reservoir, pond, lake or along a stream corresponding to some definite water level (maximum, mean, low, spillway, crest, etc.); generally used in connection with the acquisition of rights to flood lands for storage purposes.

Guard lock: a lock at the mouth of a basin or a lock for preventing flooding, usually where the canal joins a natural water course.

Hydrograph: a chart recording the changing level of water, as in a reservoir, stream, or river.

Hydrography: surveying, sounding, and charting of bodies of water; the measurement of flow and investigation of behavior of streams, especially to control or utilize their waters; the measurement of tides or currents to aid navigation.

Hydrology: the study of water on the surface of the land, in the soil and underlying rocks, and in the atmosphere, particularly in respect to physical factors such as evaporation, precipitation, stream flow, snow melt, and ground water storage.

Intermediates: when an intermediate is used in conjunction with the wet process of blueprinting it serves as a negative; blueprints made from intermediates have blue lines on a white background.

Land line: that part of a canal which is an artificial channel-- not in a river, lake or natural water bed.

Lateral canals: branch canals leading to the main channels.

Lift: the distance or extent to which water in a canal lock rises.

Lock: an enclosure with gates at each end used in raising or lowering boats passing from one level to another.

Lockage: the passage of a boat or boats through a lock; the raising or lowering of a boat from one water level to another.

Miter gates: two gates which swing together into the form of a wide letter "V".

Muck: the bottom soil in a watercourse; dark, usually black, earth that is capable of absorbing much water, often consisting of decomposing plant matter; also refers to material removed in the process of excavating.

Neat lines: the lines that bound the body of a map, usually parallels and meridians; also called sheet lines.

Offset line: a supplementary line close to and roughly parallel to a main line, to which it is referred by measured offsets; where a line for which data are desired is positioned so that it is difficult to measure over it, data are obtained by running an offset line in a convenient location and measuring offsets from it to salient points on the other line; offsets are often represented by red lines drawn across a canal in a direction that bisects the angles formed by two continuous portions of the red line (or base line) of the towing path.

Prism: the volume of water in a stream or waterway in motion considered as a shape of chosen length in conjunction with the cross section of the channel.

Red line: often a line representing the inner line of a canal towpath, upon which all the measurements in the direction of the length of the canal were made.

Siphon lock: a lock in which the water for filling and emptying is controlled by an application of the siphon principle, as distinguished from a lock filled and emptied by water controlled by valves.

Spillway: a passageway for surplus water from a canal or reservoir.

Summit level: the highest level or elevation reached.

Tow path: path along one bank of a canal where teams of men and animals worked to pull boats.

Tide water level: the level affected by the flow of the tide (in the Hudson River the tide reaches as far as Troy).

Tie: a survey connection from a point of a known position to a point whose position is desired; a tie is made to determine the position of a supplementary point whose position is desired for mapping/reference purposes or to close a survey on a previously determined point (to "tie in" is to make such a connection and the point to which the connection is made is called a tie point).

Tons capacity: the carrying content of a boat, stated in tons.

Vertical cross sections: generally found on geological maps, drawn across the map to illustrate the geological structure of the rocks through the upper levels of the earth's crust.

Waste weir: an overflow, or weir, for the escape of surplus water from a canal or reservoir; a dam-like structure along the canal berm with openings to control the water level.

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