NOVUM ORGANUM 



The First Vintage of the Form of Heat 



39' 



It must be observed that the form of anything is inherent (as 

 appears clearly from our premises) in each individual instance 

 in which the thing itself is inherent, or it would not be a form. 

 No contradictory instance, therefore, can be alleged. The 

 form, however, is found to be much more conspicuous and evi- 

 dent in some instances than in others ; in those (for example) 

 where its nature is less restrained and embarrassed, and reduced 

 to rule by other natures. Such instances we are wont to term 

 coruscations, or conspicuous instances. We must proceed, 

 then, to the first vintage of the form of heat. 



From the instances taken collectively, as well as singly, the 

 nature whose limit is heat appears to be motion. This is chiefly 

 exhibited in flame, which is in constant motion, and in warm or 

 boiling liquids, which are likewise in constant motion. It is 

 also shown in the excitement or increase of heat by motion, as 

 by bellows and drafts: for which see Inst. 29, Tab. 3, and 

 bv other species of motion, as in Inst. 28 and 31, Tab. 3. It is 

 also shown by the extinction of fire and heat upon any strong 

 pressure, which restrains and puts a stop to motion ; for which 

 see Inst. 30 and 32, Tab. 3. It is further shown by this circum- 

 stance, namely, that every substance is destroyed, or at least 

 materially changed, by strong and powerful fire and heat: 

 whence it is clear that tumult and confusion are occasioned by 

 heat, together with a violent motion in the internal parts of 

 bodies ; and this gradually tends to their dissolution. 



What we have said with regard to motion must be thus under- 

 stood, when taken as the genus of heat ; it must not be thought 

 that heat generates motion, or motion heat (though in some 

 respects this be true), but that the very essence of heat, or the 

 substantial self e of heat, is motion and nothing else, limited, 

 however, by certain differences which we will presently add, 

 after giving some cautions for avoiding ambiguity. 



Sensible heat is relative, and regards man, not universe ; and 

 is rightly held to be merely the effect of heat on animal spirit. 

 It is even variable in itself, since the same body (in different 

 states of sensation) excites the feeling of heat and of cold ; this 

 is shown by Inst. 41, Tab. 3. 



Nor should we confound the communication of heat or its 

 transitive nature, by which a body grows warm at the approach 

 of a heated body, with the form of heat ; for heat is one thing 

 and heating another. Heat can be excited by friction without 

 any previous heating body, and, therefore, heating is excluded 

 from the form of heat. Even when heat is excited by the ap- 

 proach of a hot body, this depends not on the form of heat, but 

 on another more profound and common nature; namely, that 



