318 



ON THE CULTURE 



efficacy of which, confirmed by between twenty 

 and thirty years' experience, I can safely venture 

 to recommend. 



In the year 1767 when first I came to serve His 

 Grace the Duke of Portland, I found the Pine- 

 plants in the hot-houses at Welbeck entirely over- 

 run with both the last species of insects. Know- 

 ing that I could do myself no credit in raising 

 Pines (an object of emulation amongst gardeners) 

 while these vermin remained, I became exceed- 

 ingly solicitous to extirpate them. The large hot- 

 house being at that time divided into three, by 

 glass-frame partitions, the first step I took towards 

 effecting the above purpose was to remove the in- 

 fected Pine-plants from one of the smallest of these 

 divisions. This was afterwards stocked with plants 

 from stoves clear of these vermin ; which plants 

 were proposed to be increased, and the old stock 

 in the other divisions, from time to time, rooted 

 out. But, notwithstanding every care was taken, 

 as changing the tan, washing the hot-house, &c. 

 I had the mortification to find, in the course of a 

 few months, that this stock was over-run with the 

 last species of insects. This shows that these ver- 

 min, at certain seasons, move to every part of a 

 hot-house ; it will also serve to show that too great 

 care cannot be taken in cleaning every part of the 

 hot-house, at the time of performing the operation 

 of the method of cure hereafter recommended. 



After this disappointment I endeavoured to 

 destroy these vermin by every method I had heard 



