D Y S 



300 



D Y S 



scale will obviously be increased by lengthening the 

 cy limit r anil diminishing its iliameter; or a dial pl.ite 

 M itli ;ui index may be readily applied, so as to obtain 

 the most minute subdivisions. 



In measuring the strength of the reins, we have only 

 to J'pply a hook, similar to that shewn in Fig. 7. to 

 the hook (i ; the person who exerts the force standing 

 upon a board placed at a convenient height from the 

 ground ; or the same thing may be effected by sinking 

 the vessel AB either wholly or partly into the ground. 



If we suppose the solid cylinder EF to weigh two 

 ewt and to be made of a solid whose specific gravity 

 is twice that of water, then its weight, when whol- 

 ly immersed in the fluid, will be only one cwt. and by 

 means of it all forces between one and two cwt. may 

 be accurately measured. As the specific gravity of the 

 cylinder is increased, the range of the scale will di- 

 minish in the same proportion. -A greater range of 

 scale, however, may be obtained by making the cylinder 

 hollow ; and by increasing its magnitude, any force 

 from the smallest to the greatest may be ascertained. If 

 the cylinder, for example, weighs six cwt. in air, and is 

 made so hollow as to weigh only one pound in water, 

 we have a length of scale extending from one pound to 

 six cwt 



The slightest consideration of this instrument must 

 satisfy every person, that in measuring forces where the 

 instrument itself is stationary, it is greatly superior to 

 Regnier's, and has the advantage of a natural and im- 

 moveable scale ; whereas the scale of the spring dyna- 

 mometer must be determined experimentally ; and with 

 every precaution that can be taken, the spring must to a 

 certain extent lose its elasticity, and derange the scale. 

 See Desagulier's Course of Experimental Philosophy, 

 vol. i. p. 291 ; Journal De L'Ecole Polytcchnique ; Til- 

 loch's' Philosophical Magazine, voL i. p. 399. (*") 



DYSART, the name of a royal burgh of Scotland, 

 lituated on the north side of the Frith of Forth. About 



the beginning of the 16th century, when Dysart receiv- 

 ed its charter, it was one of tin- most opulent and 

 flourishing towns in Fife ; but since that period its trade 

 has undergone several fluctuations. 



Tin- harbour, though very much exposed, is susecp- 



tible of great improvements. The trade of the town 



was formerly carried on by means of twenty-four square 



rigged vessels; but the town lias now only eight vessels 



description, and a sloop. 



The principal exports of Dysart are salt, coals, iron- 

 stone. About 17,100 I'li.-hcls of salt are annually ex 

 ported. Nearly 15,0<M) tons of coal are raised every 

 year, and about 3200 tons of ironstone are exported 

 annually to the Carron works. This ironstone yields 

 commonly 12 cwt of metal per ton of ore. About 500 

 looms are employed in the manufacture of checks, of 

 which about 530,000 yards are made annually. A num. 

 ber of hands were formerly employed in building ships, 

 but this branch of business has recently been laid aside ; 

 though, from the promising aspect of public affairs, 

 this and the other manufactures of the burgh are begin- 

 ning to revive. A greater degree of activity already 

 appears in the harbour, and it is hoped that the revival 

 of the Baltic trade will restore to Dysart its former 

 commercial importance. 



At a very short distance from the town is a mineral 

 well, which is supposed to be of the same quality as the 

 Pitcaithley water. It is covered by the sea at high 

 water during spring tides. Population of the tow 

 about 1730, and of the parish 5385. See FIFKSHIRE. 



DYSENTERY. See MEDICINE. 



DYSODIUM, a genus of plants of the class Synge- 

 nesia, and order Polygamia Necessaria. See BOTANY, 

 p. 312. 



DYTISCUS. See ENTOMOLOGY. 

 ' DYSPHANIA, a genus of plants of the class Poly* 

 gamia, and order Moncecia. See Brown's Prodromu^ 

 Sic, p. 41 1 ; and BOTANY, p. 348. 



Dysttt 



