Fustic, or Fustock, is the Dyer's MolberT-tree, or Mo-rus tinctoria, L. a native of the West Indies, whence it is brought to this country. It is used by dyers in tinging cloths of a yellow colour; for which purpose it is allowed by the 8th Geo. I. c. 15, s. 10, to be imported duty-free, excepting a convoy-duty of 7d. per cwt. - It deserves to be remarked, that a small addition of commons It renders the yellow shade darker; sal-ammoniac precipitates an orange-coloured powder, and the super-natant liquid has an aurora yellow appearance. Cloth dyed with this drug, without being previously impregnated with neutral salts, or alkalies, acquire a yellow colour of a brownish shade, which undergoes no change in the air; but M. Ber-thollet observes, that lustre and vivacity of colour can be obtained only, by preparing the stuffs with the usual solutions. - Pjrnbr, a Ger-man chemist of repute, maintains that alum, and solutions of tin, produce indeed a more lively tint, but which easily fades in the open air.