458 K0VU3I oiioANUM. [book il 



toirethor, as roses, peas in bastcts; so hay, it* it be damp when 

 elnckcd, often catches fire. 



18. Quick lime sprinkled with water. 



19. Iron, when lirst dissolved by acids in a pflass, and with- 

 out any apphcaiion to fire ; tho same of tin, but not so in- 

 tensely. 



20. Animals, particularly internally ; although tho heat is 

 not perceivable by the touch in insects, on account ot their 

 small size. 



21. Horse dung, and the like excrement from other animals, 

 when fresh. 



22. Strong oil of sulphur and of vitriol exhibit the operation 

 of heat in bnrning linen. 



23. As does the oil of marjoram, and like substances, in burn* 

 ing the bony substance of the teeth. 



24. Strong and well rectified spirits of wine exhibit the same 

 efft^cts ; so tliat white of eggs when thrown into it grows hard 

 and white, almost in the same manner as when boiled, and bread 

 becomes burnt and brown as if toasted. 



25. Aromatic substances and warm plants, as tho dracuncuhis 

 [arum], old nasturtium, &c., which, though they be not warm to 

 the touch (whether whole or pulverized), yet are discovered by 

 the tongue and palate to be warm and almost burning when 

 slijjhtly masticated. 



20. Strong vinegar and all acids, on any part of the body not 

 clothed with the epidermis, as the eye, tongue, or any wounded 

 part, or where the skin is removed, excite a pain differing but 

 little from that produced by heat. 



27. Even a severe and intense cold produces a sensation of 

 burning." 



** Nee EoreoD penetrabile frigus adurit." 



28. Other instances. 



Wo are wont to call this a table of existence and presence. 



XII. We must next present to the understanding instances 

 which do not admit of the given nature, for form (as we have 

 observed) ought no less to be absent where the given nature is 

 absent, than to be present where it is present. If, however, we 

 were to examine every instance, our labour would be infinite. 



Negatives, therefore, must be classed under the anirmatives, 

 and the want of the given nature must be inquired into more 

 particularly in objects which have a very close connection with 

 those others in which it is preseni: and manifest. And this we 

 we wont to term a table of deviation or of absence in proximity, 



■ "Ne tenues pluviae, rapidive potentia soli3 



^crior, aul Boreae penetrabile I'rigus adurat." 



Virg. Georg. i. 92. 93, 



