206 NOVUM ORGANUM. 



them thoroughly before the forms and conformations of 

 bodies have been further examined and brought to light. 

 When we have determined upon our models, we may seek, 

 apply, and arrange our instruments. 



IV. The fourth mode of action is by continuance, the very 

 steward and almoner, as it were, of nature. We apply the 

 term continuance to the abandonment of a body to itself 

 for an observable time, guarded and protected in the mean 

 while from all external force. For the internal motion 

 then commences to betray and exert itself when the external 

 and adventitious is removed. The effects of time, however, 

 are far more delicate than those of fire. Wine, for instance, 

 cannot be clarified by fire as it is by continuance. Nor are 

 the ashes produced by combustion so fine as the particles 

 dissolved or wasted by the lapse of ages. The incorpora 

 tions and mixtures, which are hurried by fire, are very in 

 ferior to those obtained by continuance; and the various 

 conformations assumed by bodies left to themselves, such 

 as mouldiness, &c. are put a stop to by fire or a strong heat. 

 It is not, in the mean time, unimportant to remark that 

 there is a certain degree of violence in the motion of bodies 

 entirely confined. For the confinement impedes the proper 

 motion of the body. Continuance in an open vessel, there 

 fore, is useful for separations, and in one hermetically sealed 

 for mixtures, that in a vessel partly closed, but admitting 

 the air for putrefaction. But instances of the operation 

 and effect of continuance must be collected diligently from 

 every quarter. 



V. The direction of motion (which is the fifth method of 

 action) is of no small use. We adopt this term, when 

 speaking of a body which meeting with another either 

 arrests, repels, allows, or directs its original motion. This 

 is the case principally in the figure and position of vessels. 

 An upright cone, for instance, promotes the condensation 

 of vapour in alembics, but when reversed, as in inverted 

 vessels, it assists the refining of sugar. Sometimes a curved 

 form or one alternately contracted and dilated are required. 

 Strainers may be ranged under this head, where the opposed 

 body opens a way for one portion of another substance and 

 impedes the rest. Nor is this process or any other direc 

 tion of motion carried on externally only, but sometimes 

 by one body within another. Thus, pebbles are thrown into 

 water to collect the muddy particles, and syrups are refined 

 by the white of an egg, which glues the grosser particles 

 together so as to facilitate their removal. Telesius, indeed, 



