244 NOVUM ORGANUM 



to the quantity; that if a leaden bullet of one ounce, for 

 instance, would fall in a given time, one of two ounces 

 ought to fall twice as rapidly, which is most erroneous. 

 Nor does the same ratio prevail in every kind of power, 

 their difference being considerable. The measure, there 

 fore, must be determined by experiment, and not by proba 

 bility or conjecture. 



Lastly, we must in all our investigations of nature ob 

 serve what quantity, or dose, of the body is requisite for a 

 given effect, and must at the same time be guarded against 

 estimating it at too much or too little. 



XLYI1I. In the twenty-fourth rank of prerogative in 

 stances we will place wrestling instances, which we are also 

 wont to call instances of predominance. They are such as 

 point out the predominance and submission of powers com 

 pared with each other, and which of them is the more ener 

 getic and superior, or more weak and inferior. For the 

 motions and effects of bodies are compounded, decom 

 posed, and combined, no less than the bodies themselves. 

 We will exhibit, therefore, the principal kinds of motions 

 or active powers, in order that their comparative strength, 

 and thence a demonstration and definition of the instances 

 in question, may be rendered more clear. 



Let the first motion be that of the resistance of matter, 

 which exists in every particle, and completely prevents its 

 annihilation; so that no conflagration, weight, pressure, vio 

 lence, or length of time can reduce even the smallest por 

 tion of matter to nothing, or prevent it from being some 

 thing, and occupying some space, and delivering itself 

 (whatever straits it be puff to), by changing its form or 

 place, or, if that be impossible, remaining as it is; nor can 

 it ever happen that it should either be nothing or nowhere. 



