172 Marine Spencer for the Prcserraibn of IJvr.r. 



who will do great things. Wc compared our herhals with 

 those of Dr. Mutis, and we consulted a great many books 

 in the immense library of that great man. We are con- 

 vinced that we have a 2;reat many new genera and species, 

 but much time and labour will be required to determiae 

 what is really new. We shall brins; with us also a siliceous 

 substance analogous to the tabasmer of the East Indies, 

 which M. Mace has analysed. It exists in the knots of a 

 gigantic gramineous plant which is confounded with the 

 Sambou, but which in its flower differs from the bamhusa 

 of Schreiber. I do not know whether Fourcrny has re- 

 ceived the milk of the vcgelallc cow, a tree so called by the 

 Indians. It is a milk which when treated with nitric acid 

 gave me a caeut-chouc of a balsamic odour, but which, in- 

 stead of being caustic and hurtful like all vegetable milks, 

 is nourishing, and agreeable to drink. We discovered it 

 in the road to Oronoko, in a plantation, where the negroes 

 drink a great deal of it. I have sent also to Fourcroy by 

 the way of Guadaloupe, as well as to sir .loseph Banks by 

 Trinidad, our dnpirhd, or white oxygenated caout-chonc, 

 which exudes from the roots of a tree in the forests of Pi- 

 michin in the most remote corner of the world towards the 

 sources of the Rio Negro. 



I shall not go to the Philippines. I shall proceed to Eu- 

 rope by Acapulco, Mexico, and the Ilavannah ; and I hope 

 to have the pleasure of seeing you at Paris in September or 

 October 1803. 



Health and respect, 



Humboldt. 



P. S. I shall be at Mexico in February, and at the Ha- 

 vaunah in June, 



XXVIII. Account of the Marine Spencer for the Preservation 

 of Lives in Cases of Shipureck or other Accidents at Sea. 

 By Knight Si'ii.scER, Esq. of Bread-street, Cheapside. 



X* OR this invention, which seems likely to be of great uti- 

 lity, the Pioyal Humane Society were pleased to award to 

 Mr. Knight their honorary silver medallion on the 25th of 

 March 180 J. 



Explanation, 



A (Plate TV.) is a girdle of a diameter to fit the body, six 

 inches broad, composed of about 800 old tavern corks, 

 .strung upon a strong twine, well lashed together with lav- 

 cord. 



