62 Dk. Macvi car's Adaptation of the Philosophy of 



decomposition, it will tend to impress its own stability and to retard or 

 arrest their decomposition. And on the other hand, let a powerful mole- 

 cule in a state of change be mixed with such as are tending that way, 

 it will assist them to change. INIoreover, in virture of its own form and 

 metamorphosis, it may also decide the change which they shall undergo- 

 In a word, we shall have the phenomena of catalysis. 



2. But in general, when dissimilar molecules are presented to each 

 other with no impediments in tiie way of their coalition, the immediate 

 effect of the law of mutual assimilation must be the merging of their 

 differences by their union, and the genesis of a new species, in which, 

 however, the types of both are preserved. In this way alone can the 

 law of assimilation accomplish all its ends, and save itself as having two 

 functions which sometimes seem to touch on the contradictory. 



And here we may remark, that a mechanical apparatus presents itself 

 by wliich chemical union shall be effected, and new species generated. 

 Thus, since the molecules which are presented to each other for union 

 are dissimilai*, the system of undulations awoke and sustained by the 

 radiant heat of each in the atmosphere of each, must also, on a general 

 view, be dissimilar. The forms and intervals of the undulse, when 

 they emanate from analogous regions in the dissimilar molecules, as 

 for instance both from equators or both from poles, must be dissimilar. 

 They will therefore not meet face to face, beat for beat ; they will not 

 act repulsively as they would do if they were of the same dimensions. 

 Hence the law of assimilation operating as the law of mutual attraction 

 will not be resisted, as it must be in the case of homogeneous mole- 

 cules. It will not be prevented from bringing dissunilar molecules very 

 near each other. But when two molecules are thus in contiguity, the 

 systems of undulations issuing from certain regions in the one, will be 

 caught by those re-entering certain I'egions in the other. What in an- 

 other region constituted an apparatus of repulsion, here constitutes an 

 apparatus of attraction. The two molecules will rush into union ; and 

 that not chaotically or accidentally, but by certain parts, viz., those in 

 which the emanating and re-entrant currents in the one and in the other 

 are of most harmonic dimensions. Thus looking to fig. H*, page 81, 

 suppose one atom of H to be as yet by itself, and so shorn of its self- 

 insulative atomosphere that others could get at its nucleus, and suppose 

 these others to accost it, then the first that comes up must be drawn 

 into the equator of the atom which was there before; for since both atoms 

 of H are similar, similar ciu-rents must emanate both from the poles of 

 each and from the equators of each. But the currents which emanate 

 from the poles of each, will be attractive to the equators of each, and 

 enter there, for the equatorial angles being formed by four lines of force, 



