154 Swallows. 



To Mr. Tillocli. 

 Sir,— In reference to the article in Dr. Thomson's Annals of 

 Philosophy, last number, on the clarifying of the syrup of the 

 sugar-cane, permit me to suinnit to you the pertinent remarks 

 of an intelligent friend of mine lately returned from Jamaica. 

 He was with Mons. Du Tmc at the moment when he received, on 

 the 13th of December 1815, the Kingston Gazette announcing 

 the award of the House of Assembly noticed in the subjoined 

 statement. 



I always am, sir. 



Yours most obediently, 

 Surry Institution, Jan. 7, 1817. J. MuRRAY. 



" The use of the bark of the hastard cedar (a tree very com- 

 BQon in all or most of the West Indian islands) was first intro- 

 duced in the purification of sugar by M.DuBoc, by birth a French- 

 man, and who had been a planter in the island of Martinique, 

 where it appears he had with great success practised the use of 

 it. M. Du Boc went to .Taniaica in the early part of 1815, where 

 he was patronized by several planters of eminence, to whom he 

 individually explained his discovery. The House of Assembly 

 of Jamaica were so thorougiiiy convinced of the benefits accruing 

 from this application of the bastard cedar bark, that in the month 

 of October 1815 they voted him a thousand pounds sterling. 



" The process is extremelv simple, and consists merely in the 

 immersion of a few strips of the bark (peeled off a branch of 

 the tree) in a bucket of water, and by squeezing the bark with 

 the hand in a short time the water becomes gelatinous, and it 

 is then thrown into the copper in which the sugar is boiling. 

 Soon after this is thrown in, the surface of the boiling sugar is 

 covered with a thick black scum, which consists of the solution 

 of the bark intermixed with tliose impurities of the sugar which 

 the lime does not precipitate — that scum is removed with a 

 scummcr in a few minutes. The sugar is afterwards drawn off 

 from the copper into the cooler, and is then considered as di- 

 vested of every impurity. 



"There grows also in Jamaica a tree, the leaf of which used in 

 the same manner produces the like effects. It is known in 

 Jamaica by the name of the JVhmigler or Wangla, but I know 

 not its specific or generic name." 



SWALLOV.S. 



On the 1 7th of February, about nine in the morning, Mr. 

 Thomas Forster observed the chimney swallow {Hmindo nis tica) 

 fiving about at Tunbridge Wells ; v.hich accords with the notion 

 eiitertahied by sowie ornithologists, that as these birds sorae- 



time5 



