108 NOVUM ORGANUM. 



penetrate, dig into, and tear asunder the parts of those 

 substances, whilst the substances themselves resist. When, 

 however, the substances yield more easily, scarcely any heat 

 is excited. 



Twenty-sixth negative to the twentieth affirmative. 



There is no negative instance with regard to the heat of 

 animals, except in insects (as has been observed), owing to 

 their small size. For in fishes, as compared with land 

 animals, a lower degree rather than a deprivation of heat is 

 observable. In plants and vegetables, both as to their 

 exudations and pith when freshly exposed, there is no sen 

 sible degree of heat. But in animals there is a great dif 

 ference in the degree, both in particular parts (for the heat 

 varies near the heart, the brain, and the extremities) and 

 in the circumstances in which they are placed, such as 

 violent exercise and fevers. 



Twenty-seventh negative to twenty-first affirmative. 



Here again there is scarcely a negative instance. I might 

 add that the excrements of animals even when they are no 

 longer fresh, possess evidently some effective heat, as is 

 shown by their enriching the soil. 



Twenty-eighth negative to the twenty-second and twenty-third affirmative. 



Such liquids (whether oily or watery) as are intensely 

 acrid exhibit the effects of heat, by the separation and 

 burning of bodies after some little action upon them, yet 

 they are not at first warm to the touch. But they act ac 

 cording to their affinity and the pores of the substances to 

 which they are applied. For aqua regia dissolves gold but 

 not silver, on the contrary, aqua fortis dissolves silver but 

 not gold; neither of them dissolves glass, and so of the 

 rest. 



Twenty-ninth negative to twenty-fourth affirmative. 



Let spirits of wine be tried on wood, or butter, wax, or 

 pitch, to see if this will melt them at all by their heat. For 

 the 24th instance shows that they possess properties re 

 sembling those of heat in causing incrustation. Let an 

 experiment also be made with a graduated glass or calendar* 

 concave at the top, by pouring well rectified spirits of 

 wine into the cavity, and covering it up in order that they 

 may the better retain their heat, then observe whether their 

 heat make the water descend. 



Thirtieth negative to twenty-fifth affirmative. 



Spices and acrid herbs are sensibly warm to the palate, 

 and still more so when taken internally. One should see, 



* See No. 38 in the table of the degrees of heat. . 



