Influence of Astrology. 83 



appears that by grafting and other more 

 occult processes, he endeavoured to modify 

 the colour and flavour of fruit, and to bring 

 it forward, so that, for instance, the grape 

 and the cherry might be ready at the 

 same time, which the mediaeval expert 

 sought to accomplish by grafting a vine slip 

 on a cherry stock. The use of clay in graft- 

 ing was already familiar. But seeing how 

 imperfectly this important branch of the 

 science is at present understood, we need not 

 wonder at the rudeness of its development 

 in the middle ages. 



In Bacon's time tender fruit and other 

 trees appear to have been protected by some 

 system of stove, as he tells us in a passage 

 of his Essays, already quoted ; but neither 

 Evelyn nor Worlidge goes beyond a hot-bed 

 constructed in the ordinary way for bottom 

 heat, and screened from the weather at night, 

 or during the prevalence of frost, by an arched 

 canopy of thatch or matting. Worlidge 

 thought that the best description of a hot- 

 bed which he had yet (1677) seen was in 

 Evelyn's Philosophical Discourse of Earth, 



