THE VEGETABLE KINGDOM. 551 



time it was not possible to A^erify any change in its cir- 

 cnmference. It was accurately measured in 1402 by tlie 

 companions of Bethencourt at the time Avhen they dis- 

 covered the island, that is to say, more than 460 years 

 ago, and since then it has in no way increased in diameter. 

 Time has passed over without touching it. Humboldt, 

 when he ascended the peak of Teneriflfe in 1799, measured 

 this tree a little above the level of the ground, and found 

 it forty-five feet in circumference. 



CHAPTER IV. 



DENSITY OF PLANTS. 



As the duration of life in trees presents such vastly 

 opposite limits, we expect to meet equally enormous 

 diflTerences in their density; and this is the case. 



Those singular plants the Tremellaj, which after a wet 

 night, or even merely a storm, suddenly bestrew the earth 

 in the shape of so many tremulous masses of jelly, coA^ering 

 the ground where a few hours before there was not a 

 vestige, and Avhich, on account of the imexpected manner 

 in which they appear, were looked upon by the alchemists 

 as a supernatural production, an emanation from the 

 stars, are so soft that the least pressure crushes and 

 reduces them to water. ^ 



1 The supposed supernatural origin of tlie ti-emel)a iiostoc {A'ostoo commune) 

 led the alchemists to employ it in their search after the philosopher's stone. 

 The peasants also referred its origin to the stars. But less nice in their language 

 than the adepts in the great work, they merely called this singular fungus moon- 

 spittle. 



70 



