HAR 



HAR 



ration of its particles. This property de- 

 pends on the force of cohesion, or on that 

 which chemists call affinity, joined to the 

 arrangement of the particles to their 

 figure, and other circumstances. A body, 

 says M. Hauy, is considered more hard, in 

 proportion as it presents greater resist- 

 ance to the friction of another hard body, 

 such as a steel file ; or as it is more capa- 

 ble of wearing or working into such other 

 body to which it may be applied by fric- 

 tion. Lapidaries judge of the hardness 

 of fine stones, &c. from the difficulty 

 with which they are worn down or po- 

 lished. 



HARE. See LEPUS. 



HARIOT, or HE RIOT, in law, a due be- 

 longing to a lord at the death of his te- 

 nant, consisting of the best beast, either 

 horse, ox, or cow, which he had at the 

 time of his death ; and in some manors, 

 the best goods, piece cf plate, &.c. are call- 

 ed hariots. 



There is both hariot- service, and hariot- 

 custom : when a tenant holds by service 

 to pay a hariot at his decease, which is ex- 

 pressly reserved in, the deed of feofment, 

 this is a harlot-service ; and where ha- 

 riots have been customarily paid time out 

 of mind after the death of a tenant for 

 life, this is termed hariot-custom. For ha- 

 riot-service, the lord may distrain any 

 beast belonging to the tenant that is on 

 the land. For hariot-custom, the lord is 

 to seise, not distrain ; but he may sgise the 

 best beast that belonged to the tenant, 

 though it be out of the manor, or in the 

 king's highway, because the claim is, as 

 his proper goods by the death of his te- 

 nant. Nevertheless, where a woman mar- 

 ries and dies, the lord shall have no hariot- 

 custom, because a feme-covert has no 

 goods to pay as a hariot. 



HARMATTAN, the name given to a 

 singular wind, which blows periodically 

 from the interior parts of Africa towards 

 the Atlantic ocean. It prevails in Decem- 

 ber, January, and February, and is gene- 

 rally accompanied with a fog or haze that 

 conceals the sun for whole days together. 

 Extreme dry ness is the characteristic of 

 this wind : no dew falls during its con- 

 tinuance, which is sometimes for a fort- 

 night or more. The whole vegetable 

 creation is withered, and the grass be- 

 comes at once like hay. The natives take 

 the opportunity which this wind gives 

 them of clearing the land, by setting fire 

 to trees and plants in this their exhausted 

 state. The dryness is so extreme that 

 household furniture is damaged, and the 

 wainscot of the rooms flies to pieces. 

 The human body is also affected by it, so 



VOL Vli 



as to cause the skin to peel off; but in 

 other respects it is deemed salutary to the 

 constitution, by stopping the progress of 

 infection, and curing almost all cutaneous 

 diseases. 



HARMONICA, or ABMOJTICA, is a name 

 which Dr. Fanklin has given to a musical 

 instrument constructed with drinking 

 glasses. It is well known that a drinking 

 glass yields a sweet tone, by passing a wet 

 linger round its brim. Mr. I'ockrich, of 

 Ireland, was the first who thought of play- 

 ing tunes formed of these tones. He col- 

 lected a number of glasses of different 

 sizes, fixed them near each other on a ta- 

 ble, and tuned them by putting into 

 them water, more or less, as each note re- 

 quired. Mr. Delaval made an instrument 

 in imitation, and from this instrument Dr. 

 Franklin took the hint of constructing his 

 Armonica. The glasses for this musical 

 instrument are blown as nearly as possi- 

 ble in the form of hemispheres, having 

 each an open neck or socket in the mid- 

 dle. The thickness of the glass near the 

 brim is about one tenth of an inch, increas- 

 ing towards the neck, which in the larg- 

 est glasses is about an inch deep, and an 

 inch and a half wide within; but these 

 dimensions lessen as the size of the glasses 

 diminish, only observing that the neck of 

 the smallest should not be shorter than 

 half an inch. The diameter of the largest 

 glass is nine inches, and that of the small- 

 est three inches : between these there are 

 twenty-three different sizes, differing 

 from each other a quarter of an inch in 

 diameter. For making a single instru- 

 ment there should be at least six glasses 

 blown of each size, and out of these thir- 

 ty-seven glasses (which are sufficient fdr 

 three octaves with all the semitones) may 

 be found, that will either yield the note 

 required, or one a little sharper, and fit- 

 ting so well into each other, as to taper 

 regularly from the largest to the smallest. 

 The glasses being chosen, and the note 

 for which each glass is intended being 

 marked upon it with a diamond, they are 

 to be tuned, by diminishing the thickness 

 of those that are too sharp, which is done 

 by grinding them round from the neck 

 towards the brim ; comparing, by means 

 of a well-tuned harpsichord, the tone 

 drawn from the glass by your finger with 

 the note you want, a* sounded by the 

 corresponding string of the harpsichord. 

 The largest glass in the instrument is G, 

 a little below the reach of'a common voice, 

 and the highest G, including three com- 

 plete octaves ; and they are distinguished 

 by painting the apparent parts of the 

 glasses within side, every semitone white^ 



P 



