142 



while on the road from Santa Cruz to Laguna 

 the plants exhibited nothing but pods emptied 

 of their seeds. Near the port of Santa Cruz, the 

 strength of the vegetation is an obstacle to geo- 

 logical researches. We went on foot over two 

 small hills, which rise in the form of bells. Ob- 

 servations made at Vesuvius, and in Auvergne, 

 lead us to think, that these paps owe their ori- 

 gin to lateral eruptions of the great volcano. 

 The hill called Moniannita de la Villa seems in- 

 deed to have already emitted lavas ; and accord- 

 ing to the tradition of the Guanches this erup- 

 tion took place in 1430. Colonel Franqui as- 

 sured Borda, that the place is still to be seen 

 whence the melted matter issued ; and that the 

 ashes, which covered the ground adjacent, were 

 not yet productive # . Wherever the rock ap- 

 pears, we discovered basaltic amygdaloid co- 



* This fact is taken from a manuscript now at Paris, at the 

 dep6t of the Charts of the Marine. It bears the title of Re- 

 sume des Operations de la Campagne de la Boussole (in 1776) 

 pour determiner tes Positions geographiques des Cotes oVEspagne 

 Sf de Portugal sur VOcean^ aVune Partie des Cotes occidentales 

 de VAfrique, des Iks Canaries, par le Chevalier de Borda. 

 This is the manuscript of which Mr. Fleurieo speaks in the 

 notes, which he has added to the Voyage of Marchand, vol. 

 ii, p. 11, and which M. de Borda had communicated to me 

 previous to my departure. As I have extracted some impor- 

 tant observations from it, which have never been published, 

 I shall cite it in this work under the title of Manuscript du 

 Depot. 



f Basaltartiger mandelstein. Werner. 



