Show laughter Laug liter a series of barks laughing Is barking say tho sa enlists entis ts tho the neck and head aro are thrown back while a series of chrt albort barks are emitted from the throat threat however musical the barks may tie be they are barks barka the laugh begins with a sudden and violent contraction of tile tho inus muscles ales ot the chest and abdomen rut but instead of hopeni opening n g 6 to 8 let i the air pass out oh of the lungs the vocal cords approach each other and holdst bold it back but they are not strong enough to exercise such opposition fr for more etiore than an instant and the air i which under tinder pressure promptly escapes As aa it does so it makes the vocal cords cordi vibrate producing the bark this obstruction and liberation of the air expelled from the lungs repeats itself again and again at interval fl of a quarter of a second there nr arethus ethus in a hearty laugh four barks a second and if continued they goon rate as long as the air reserve in the lungs holds out the empty lungs must then fill themselves and this this interval Is marked by a quick gasp for breath after affer which the barks ard arbre e dewed tile the barks occur in series with gasps for breath at intervals interval s when laughter Is violent tile the entire body participates part of th the e trunk bends and straightens tens itself alternately or sways to right and aninett the feet stamp on the floor while the hands are pressed upon the loins loing to moderate the painful spasm |