HAILMAT'TAN, the name given to a prevailing wind on the coast of Africa, which is of a peculiarly dry and parching character.
HA li.MON'ICA, or AR MONICA, a musical instrument, in which the sound is produced from glasses, blown as near as possible in the form of hemispheres, having each an open neck or socket in the middle. 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, difrering from each other a quarter of an inch in diameter. The largest glass in the in strument is G, including three complete octaves ; and they are distinguished by painting the apparent parts of the grass es within side, every semitone white, and the other notes of the octave with the seven prismatic colors ; so that glass es of the same color, (the white except ed,) are always octaves to each other. The method of extracting exquisite tones, by rubbing the finger on the brim of drinking,-glasses, filled with water in dif ferent proportions, was an old discovery; but it remained for Dr. Franklin to c.m
street the harmonica. advantages of this instrument," says Dr. Franklin, "are, that its tones ace incomparably sweet beyond any other; that they may be swelled and softened at pleasure, by stronger or weaker pressures of the fin ger, and continued to any length ; and that the instrument, once well tuned, never again wants tuning." Its disad vantages are, the difficulty of adjusting the tones by grinding ; the extreme skil necessary in the player ; and the impracticability of performing upon it many of the ordinary operations of the musical art ; for however much it excels all others in the delicacy anilduration (X its yet it is confined t3 those of a soft and plaintive character, and to slow solemn movements.