TIE A 



3B8 



TIEE 



formerly appointed to take cr.rc of the 

 cattie of a manor, and preserve the 

 hedges from them. 



HEAD. The head of a ship is an orna- 

 mental figure, erected on a continuation 

 of the stem, and is emblematic of the 

 ship's name. A head of water is a regular 

 height of water intended for the supply 

 of mills, fountains, and the<ke. 



HEAD'BOROUGH. Sax. borg, pledge. The 

 chief of the ten pledges in frank-pledge. 



HEADERS. In building, stones extend- 

 ing over the thickness of a wall, or bricks 

 laid lengthways across the thickness. 



HEADING. 1. In mining, &c. See DRIFT. 



2. In building, a course consisting of 



headers or stones, bricks or the like, laid 

 lengthways across the thickness of the 

 wall, called heading-courses. 



HEADING-STONE. See KETSTOXK. 



HEADLAND. In geography, nearly syno- 

 nymous with cape or promontory. In 

 agriculture, a border at the sides of a field, 

 to afford space for turning the plough. 



HEAD'WAT, a name for the clear 

 height of an arch, &c. 



HEAD'WORK, a name for ornaments on 

 the keystones of arches. 



HEA.LDS, the harness for guiding the 

 warp threads in a loom ; more commonly 

 fuddles. 



HEART, Germ. here. The human heart 

 is a hollow muscular organ, of a coniform 

 shape ; the broad part is the base, the 

 smaller end is the apex. 



HEART'-BOUND. In building, is where 

 two stones forming: the breadth of the 

 wall, have one stone of the same breadth 

 placed over them. 



HEART WHEEL, a mechanical contriv- 

 ance, common in cotton mills, for con- 

 verting a circular motion into an alter- 

 nate rectilinear motion. 



HEART WOOD. In botany, duramen, the 

 central part of the trunk of a tree. 



HEAT, as a sensation, is the effect pro- 

 duced on the sentient organs of animals 

 by the passage of caloric ; as a cause of 

 sensation, it is regarded as a subtle fluid 

 contained in greater or less degree in all 

 bodies (see CALORIC.) Heat is latent when 

 combined with matter so as not to be 

 perceptible and sensible, or free when it is 

 evolved and perceptible. 



HEATH'ER, a name in Scotland for heath. 



HEAVE. In navigation, to employ a 

 force to move great weights ; as to heave 

 tip the anchor by the capstan ; to heat* 

 down the ship, or pull her over on one 

 side to get at a leak ; to heaie taught, or 

 turn the capstan till the rope becomes 

 tight ; to heave to or bring the ship's head 

 to the wind. 



HEAV'EN, the expanse which appears to 

 mirround the earth like an immense vault, 

 and in which the sun, moon, and stars 

 are *eea, and thence called heavenly 



bodies. The ancient astronomers enume- 

 rated as many hc-avcns ar, they i 

 motions. Thus each planet had its heaven, 

 and an eighth heaven was laid out for 

 the fixed stars. 



HEAV'Y SPAR, a name for sulphate of 

 baryta or baro-selenite, of which there 

 are several varieties, as compact and 

 fibrous heavy spar ; straisht and curved 

 lamellar heavy spar; earthy, hepatic and 

 prismatic heavy spar. It takes its name 

 from its high specific gravity, which 

 ranges from 4'3 to 4'5. It occurs in veins 

 plentifully throughout Europe. 



HECATOM'PEDON, from ixetrn, a hun- 

 dred, and vov;, a foot. A temple of a 

 hundred feet in height. 



HECATON'STYLON, from IZOITM, a hun- 

 dred, and tTTufai, a column. A temple 

 having a hundred columns. The name 

 was chiefly applied to a celebrated gallery 

 at Rome. 



HECK'LE, an instrument for dissevering: 

 the filaments of flax. See HACKLE. 



HEC'TARE, a French land measure con- 

 taining a hundred ares : whence the name. 



HECTIC, Lat. hecticus, habitual, from 

 i|<j, habit. The term is used to denote a 

 slow continual fever, marked by preterna- 

 tural, though remitting heat, often symp- 

 tomatic of phthisis. Hectic fever is one 

 of the many diseases which the art of 

 medicine has hitherto laboured in vain to 

 strike at by a direct mode of c-ure. The 

 real cause of it is commonly involved in 

 impenetrable obscurity. 



HEC'TOORAM, a French weight eqnal to 

 100 grams. 



HEC'TOLITRE, a French measure of ca- 

 pacity for liquids, equal to 100 litres. 



HECTOM'ETRE, a French measure equal 

 to 100 m^res. 



HED'ERA, the ivy. A genus of perma- 

 nent plants. Pentandria Hlonogynia. 

 Name from heereo to stick, on account of 

 its adhering to walls, &c. Three species. 

 Europe. 



HEDERA'CEJE, a natural order of plants, 

 consisting of the ivy (hederii), and a few 

 allied genera. 



HEDGE-HOG. I. In zoology. See ERINA- 



CEUS. 2. The name given to a machine 



for removing mud, silt, &c., from rivers 

 and streams. It consists of a roller with 

 spikes on its circumference, and being 

 dragged along acts upon the bottom. 



HEDYS'ARCM, a very extensive genus 

 of papilionaceous plants. Diadelphia 

 Decandria. Name from viou;, sweet. The 

 manna plant (H. alkadi) being a species. 

 All parts of the world. The cock's-head 

 is the only British type. 



HEEL (of a rafter), the end or foot whicX 

 rests upon the wall-plate. Also the aft 

 end of a ship's keel. To heel over, to in 

 dine to one side. 



