320 



DISEASES 



Sect. XIV. I. 2. 



killed in England. Perhaps thofe in France having been accuftomed 



much hotter fummers were unable to endure th 



fa 



rigour of 



me winter, that did not deftroy the fame plants in England 



faid 



have found, that th 



Horfe-hoeing Hufbandry, Ch. XIII. p. 

 By adapted experiments Medicus is 

 irritability of plants is greater in the morning, lefs in the middle of 

 the day, and much lefs in the evening. And Von Uflar found, that 

 their irritability in refpe6l to their contradions was increafed in cool 

 and rainy weather. Obferv. on Plants by Schmeiffer. Edinb. So the 

 parts of animals become more fenfible to heat after having been pre- 



glow on coming into the 



fly expofed to cold ; as our hand 



houfe after having for a while been immerfed in 

 1 



fnow 



and 



many 



nfe<5ts, and other animals, which hide themfelves in the earth, and 

 fleep during the winter, were obferved by M. Spallanzani to difappear 

 at a feafon, when the heat of the atmofphere was much higher 

 than in the fpring, when they again made their appearance. 



Hence 



follows, that pi 



which are kept in a warm room 



during winter, fliould occafionally be expofed to cooler air to increafe 



their irritabihty 



otherwife their growth in the fpring is obferved 



to be very tardy. Mankind for the fame reafon requires the perpe 

 tual variations of the heat of the atmofphere to preferve or reftore th 



tability 



nd 



feq 



6livity, of th 



fyftem 



Wh 



th 



health and energy of men are greater, and their lives longer, in th 

 variable ifland, than in the tropical continents, which pofTefs o-reat( 



2. 



mth, and lefs variation of weath 

 Linneus in the Philofophia B 



■^ 



h 



as 



given names to b 



four internal difeafes, eurifiphe, mildew ; rubigo, ruft ; clavus, ergot, 

 or fpur ; and uftilago, fmut ; to which may be added many others as 

 defcribed below. 



Eryfiphe, a white mucor, or mould, or mildew, with feffile 

 tawny heads, with which the leaves are fprinkled ; this is frequent 



in humulus, hop ; lamium, dead nettle ; gallopfis, arch-angel ; li- 



thofpermum, 



