348 Dynamic Theory. 



give rise to a divergence of chemical and physical reactions ; and the 

 logical sequence of this is, that traced to ultimate conditions, the only 

 difference between atoms may consist in difference of form. We shall 

 find many facts which point to such conclusion. If that is the case, it 

 will follow further that all their supposed properties, affections, affin- 

 ities, &c. , are merely diverted forms of external energy, and come into 

 existence as such, or go out, according to the manner in which they are 

 assailed by external energy. This is true of the great artificial machines, 

 as everyone will admit without argument and it is true of the great or- 

 ganisms, as can be proved, if need be. What is true of the great may 

 be equally true of the small. That the influence of form is paramount, 

 in some oases, at least, is proved by the facts of allotropism and isomer- 

 ism. The meaning of the first term is " of another habit," and it is 

 applied in the case of those elementary bodies which show themselves 

 in more than one form. Some examples of allotropism will be men- 

 tioned. Oxygen has three habits of existence ; viz. , as oxygen, ozone, 

 and antozone. Ozone is once and a half as heavy as oxygen, and has 

 most of the properties of oxygen intensified. It has an odor like sul- 

 phur. A molecule of common oxygen has two atoms, while a molecule 

 of ozone has three. Ozone is formed from oxygen by heat, by light, 

 and by electricity, and is often detected in the air after a thunder-storm, 

 by its odor. At a temperature of 290 it is reconverted into oxygen. 

 Antozone is formed whenever ozone is, and is changed to oxygen by be- 

 ing heated. It is a great agent in the formation of fogs and clouds 

 with water. Thus the difference between these three is very consider- 

 able, and they have quite different affinities, yet are interconvertible 

 into one another ; in fact, are three habits of the same thing made 

 different by different external conditions. 



Phosphorus is an elementary body which without losing its name may 

 occur in two different allotropic states. In the ordinary state it is called 

 Alpha Phosphorus. It is colorless and it forms into twelve-Sided crys- 



FIG. 150. 



FIG. 150. Crystals of Sulphur. 

 1, 2. Alpha sulphur. 

 3. Beta sulphur. 



FIG. 149. 



FIG. 149. Phosphorus Crystals. 

 \.~Alpha Phosphorus. 

 2. Beta Phosphorus. 



tals, fig. 149, 1. Its specific gravity is 1.83, it melts at 44 and boils 

 at 290. In the air at 50 it takes fire. It is violent poison. Heat of 250 



