HAK 



HAL 



Carbonate of ammonia . 90 



Water 179 



Oil 288 



Gases 271 



Coal 324 



1152 



The oil was soluble in alcohol, burnt 

 with brilliancy, and with scintillations like 

 the hair itself. The coal was attracted by 

 the magnet, which proves it contains 

 iron. The alkalies, at a boiling heat, dis- 

 solve hair, and form with it an animal 

 soap. Sulphuric acid dissolves hair, with 

 the aid of heat. Hair is usually distin- 

 guished into various kinds : the stiffest 

 and strongest is called bristles, such as 

 that on the backs of swine. When re- 

 markably soft and pliable, it is denominat- 

 ed wool, as that on sheep ; and the finest 

 of all is called down. From wool more 

 than half its weight of oxalic acid is ob- 

 tained. Feathers possess similar proper- 

 ties to those of hair ; the quill is composed 

 of coagulated albumen, but no gelatine. 

 Muriatic acid dissolves hair, and the so- 

 lution is very like a solution of glue in the 

 same acid. When plunged into acid, in 

 the state of gas, it is very soon converted 

 into a pulp. 



HAIII, or DOWN, of plants, a general 

 term, expressive of all the hairy and glan- 

 dular appearances on the surface of plants, 

 to which they are supposed by naturalists 

 to serve the double purpose of defensive 

 weapons and vessels of secretion. These 

 hairs are minute threads, of greater or 

 less length and solidity, some of them vi- 

 sible to the naked eye, whilst others are 

 rendered visible only by the help of glass- 

 es. Examined by a microscope, almost 

 all the parts of plants, particularly the 

 young stalks or stems, appear covered 

 with hairs. Hairs on the surface of plants 

 present themselves under various forms ; 

 in the leguminous plants they are gene- 

 rally cylindric ; in the mallow tribe, ter- 

 minated in a point ; in agrimony, shaped 

 like a fish-hook; in nettle, awl-shaped 

 and jointed ; and in some compound flow- 

 ers, with hollow or funnel-shaped flo- 

 rets, they are terminated in two crooked 

 points. 



HAIR'S breadth, a measure of length, be- 

 ing the forty-eighth part of an inch. 



HAKE, in ichthyology, the English 

 name of the gadus, with two fins on the 

 back, and the under jaw longest. It 

 grows to two feet or more in length, but 



is the slenderest of all the gadi. See 

 GADUS. 



HALBARD, or HALBEKT, in the art of 

 war, a well-known weapon, carried by 

 the Serjeants of foot and dragoons. It is 

 a sort of spear, the shaft of which is about 

 five feet long, and made of ash or other 

 wood. Its head is armed with a steel 

 point, edged on both sides> not unlike the 

 point of a two-edged sword : but besides 

 this sharp point, which is in a line with 

 the shaft, there is a cross piece of steel, t 

 flat, and pointed at both ends ; but gene- 

 rally with a cutting edge at one extremi- 

 ty, and a bent sharp point at the other; 

 so that it serves equally to cut down, 

 or push withal. It is also useful in 

 determining the ground between the 

 ranks, and in adjusting the files of a bat- 

 talion. 



HALE, in the sea language, signifies 

 pull ; as to hale up, is to pull up ; to hale 

 in or out, is to pull in or out. To over- 

 hale a rope, is to hale it too stiff, or to 

 hale it the contrary way. 



HALES, (STEPHEN,) D. D. in biogra- 

 phy, an eminent natural philosopher and 

 excellent parish clergyman, was sixth son 

 of Thomas Hales, Esq. of Beckesbourn, 

 in Kent, where he was born in 1677. At 

 the age of nineteen he was entered a 

 pensioner of Bene't College-, Cambridge, 

 of which he was elected a fellow in 1702. 

 He afterwards proceeded M. A. and 

 entered into holy orders. During his resi- 

 dence at Cambridge, he distinguished 

 himself by his diligent researches into 

 various branches of natural knowledge, 

 particularly botany and anatomy. In these 

 studies he had for an associate William 

 Stukely, afterwards M. D. and an emi- 

 nent antiquary. A turn of novel and in- 

 genious experiments, and of mechanical 

 inventions, early characterised Mr. Hales, 

 and a contrivance for obtaining a prepa- 

 ration of the lungs in lead, with the con- 

 struction of a planetarium upon the New- 

 tonian system of astronomy, are mention- 

 ed among the products of his skill at this 

 period. In 1710 he was presented to the 

 perpetual curacy of Teddington, in Mid- 

 dlesex. Not long after he vacated his 

 fellowship by accepting the living of Port- 

 lock, in Somersetshire, which he ex- 

 changed for that of Farringdon, in Hamp- 

 shire. He then married the daughter of 

 a clergyman, who died after two years, 

 leaving no issue. Henceforth he lived 

 entirely' as a single man, devoting himself 

 entirely to science, and objects of public 

 utility. In 1717 he was elected a mem- 



