LOC 



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LOG 



of thi> piece 2. The barrier or works 



of a canal, which confine the water where 

 a change of level takes place, and for 

 passing the boats from one level to an- 

 other. Canal locks are provided with 

 gates at each end, and are made suffi- 

 ciently large to receive the largest boats 

 navigating the canal upon which they 

 are constructed. The upper portion of 

 the canal is generally termed the upper 

 pond, and the other the lower pond ; the 

 difference between the levels is the lift of 

 the lock ; the portion of the lock inclosed 

 by the gates is the lock-chamber ; the re- 

 cesses into which the leaves of the gates 

 turn are termed gale-chambers; the gate- 

 post hung in the hollow quoin is called 

 the quoin or heel-post, and the other the 

 mitre-post ; the bottom framings against 

 which the gates shut are termed mitre- 

 sills, and are either upper or lower; the 

 bays are the portions of a lock at each ex- 

 tremity of the lock-chamber: they are 

 either fore or tail bays accordingly. 



LOCK'ER. A kind of strong-box or chest 

 made along the side of a ship, to stow 

 anything in. 



LOCK-GATES. The framed gates employed 

 on rivers and canals, for penning back the 

 water and forming locks. They consist 

 commonly of two leaves, and are opened 

 cither by means of balance-beams, situ- 

 ated on the top of the gates, or by boat- 

 hooks; a large gate, running upon wheels, 

 is opened by means of a windlass and 

 chain. They are termed upper and lower 

 gates, according to their situation. 



LOCK-PADDLE. A small sluice, by which 

 an empty lock is filled. 



LOCK-SILL. An angular piece of timber 

 at the bottom of a lock, against which the 

 gates shut. See LOCK. 



LOCK-WEIR, paddle-weir. \ . An overfall 

 behind the upper lock-gates, by which the 

 waste water of the upper pond is let 

 down through the paddle-holes into the 



lock-chamber. 2. A weir furnished 



with a lock. 



Lo'coro'cos. The designation of the 

 ultra-democratical party in America, 

 since 1834. 



LOCOMO'TIVE ENGINE. A motive steam- 

 engine, usually constructed on the high- 

 pressure principle, employed in land- 

 carriage, chiefly of railways. 



LOCOMO'TIVE POWER is any power ap- 

 plied directly to the transport of goods, in 

 distinction from stationary power. 



LOC'ULAMENT, Lat. loculamenfiim. A 

 lodgment. A term, in botany, for the cell 

 of a pericarp in which the seed is lodged. 



LOCPLI'CIDAL. In botany, a particular 

 kind of dehiscence. Some fruits open by 

 the dividing of each carpellum at its mid- 

 rib, so that the dissepiments stick together, 

 *.&<? to two halves of contiguous carpella : 

 this is called ivctuicida* tUUtCMM 



LO'CUM TE'NENS. One who fuidt tht 

 place of another ; a deputy. 



Lo'cus, a place. Locus in quo, ths place 

 where anything is alleged to be done in 

 legal pleadings, &c. Lows partibus, a di- 

 vision made between two counties, &c. to 

 make trial where the place in question 

 lies. 



LO'CUST. 1. In botany, a name applied 

 to the spikelet of grasses. 2. In ento- 

 mology, see CICADA, and ACRYDITJM. 

 , LO'CUST-TREE. The pseud-acacia, or 

 common robinia,a tree of North America. 



LODE. In mining, a vein of ore, from 

 Sax. laedan, to lead. The term is used to 

 signify a regular vein or course, whether 

 metallic or not ; but most commonly it is 

 applied to a metallic vein. The lodes are. 

 said to be alive when the ores are good . 

 and dead, when the gangue is the only 

 material found. 



LODGE, Fr. logis. In architecture, & small 

 house in a park or domain, subordinate to 

 the mansion ; also, the cottage at the gate 

 of the avenue. 



LODGED. In heraldry, a term for a buck, 

 hart, &c., when lying on the ground ; an- 

 swering to couchant, which is applied to 

 beasts of prey, as a lion. 



LODG'MENT. In fortification, a work 

 raised with earth, gabions, fascines, &c., 

 to cover the besiegers from the enemy's 

 fire, and enable them the better to hold 

 a position which they have taken. 



LOESS. A German word, used by geolo- 

 gists to designate an alluvial tertiary de- 

 posit, consisting of calcareous loam. It 

 is exemplified between Cologne and Basle. 



LOG. A machine for measuring the rate 

 of a ship's velocity through the water. 

 The common log is a piece of board, form- 

 ing the quadrant of a circle, about six 

 inches radius, balanced by a small plate 

 of lead, nailed on the circular part, so as 

 to swim perpendicularly in the water, 

 with the greater part immersed. To this 

 is attached a log-line, which, when the log 

 is " heaved," is unwound from its reel by 

 the log, which remains stationary in the 

 water, while the ship moves away : the 

 number of " knots" run off in half-a- 

 minute, denotes the number of miles 

 which the ship is making per hour. The 

 observations are marked on the log-board. 

 The log-board consists of two boards, 

 shutting together like a book, and is di- 

 vided into columns, containing the hours 

 of the day and night, the directions of the 

 winds, the courses of the ship, and what 

 ever material occurrences happen during 

 the twenty-four hours. The contents of 

 the log-board, being written with chalk, 

 are wiped out at noon, having been first 

 transcribed into the log-book, which is 

 duly signed by the commanding-officer. 



LOO'ARITHX, from t-o-yo;, ratio, ar.< 

 (#itf , number. Ratio of numbers. Lo- 



2F2 



