722 REPORT-—1896. 
atoms of the whole assemblage. The next simplest case is that in which there are 
two kinds of atom, /, 0, with the distinction that the force between two /’s and 
the force between two o's and the force between an / and an o are generally 
different at the same distance. The mutual force between two h’s is, of course, 
always the same at the same distance. So also is the mutual force between two 
o’s and between an / and an o, 
The object of the present communication is to find how much of the known 
properties of the substances named in the title can be explained with no further 
assumption except the conferring of inertia upon a Boscovich atom. 
The known chemical and physical properties to be provided for are: 
1, That in each of the gases named the molecule is divisible into two; which 
is the meaning of the symbols H,, O,, used to denote them in chemistry. 
2. That Ozone (Q,) is a possible, though not a very stable, gaseous molecule, 
consisting of a group of Oxygen atoms of which the constituents readily pass into 
the configuration (O,) of Oxygen gas. 
3. That Peroxide of Hydrogen (H,O,, or perhaps HO) is a possible, but not a 
very stable, combination, which, for all we know, may exist asa liquid ora dry gas, 
but which is only generally known as a solution in water (of density 1:45 in the 
highest concentration hitherto reached), readily absorbing Hydrogen or parting 
with Oxygen so as to form H,O. 
4, That water (H,O) is an exceedingly stable compound in the gaseous, liquid, 
or crystalline form, according to circumstances of temperature and pressure, 
5. That dry mixtures of Hydrogen and Oxygen gases, and also mixtures of 
these gases with water in the same inclosure, have been kept by many experi- 
menters for weeks or months, and perhaps for years, inclosed in glass vessels, 
without any combination of the two gases having been detected. 
6. That Ice contracts by about 8 per cent. in melting, and that ice-cold water, 
when warmed, contracts till it reaches a maximum density at about 4°C., and 
expands on further elevation of temperature. 
7. For Quartz crystal— 
(a) The difference between neighbouring corners of the hexagonal prism. 
(0) The similarity between each face and its neighbour on either side turned 
upside down (the axis of the prism supposed vertical). 
(c) The right-handed and left-handed chiralities of different crystals in nature 
with, so far as known, an equal chance of one chirality or the other in any crystal 
that may be found. 
In the present communication it is shown that all the properties stated in this 
schedule can be conceivably explained by making H consist of two Boscovich atoms 
(h, h), and O of two others (0, 0). This essentially makes H, consist of four /’s at 
the corners of an equilateral tetrahedron, and O, a similar configuration of four o’s. 
It naturally shows Ozone as six o’s at the corners of a regular octahedron. It makes 
H1,0 (the gaseous molecule of water) consist of two o’s with two /’s attached to 
one of them and two other /’s attached to the other; the /’s of each o getting as 
near to the other o as the mutual repulsion of the A’s allows. This configuration 
and the modification it experiences in the formation of crystals of ice are illus- 
trated by models which accompany the communication. 
To understand what is probably the true configuration of ice-crystal, we are 
helped by first considering a double cubic assemblage of point-atoms, such that 
each point-atom isin the centre of a cube having eight point-atoms for its corners. 
This double cubic assemblage may be imagined as consisting of two simple cubic 
assemblages, so placed that one atom of each assemblage is in the centre of a 
cube of atoms of the other. The annexed diagram shows, in the centres of the 
circles which it contains, atoms of a double cubic assemblage, which lie in the 
plane of a pair of remote parallel edges, A D, B C, of one set of constituent cubes. 
It shows all the atoms in the lines of this plane which it contains except certain 
omissions in the lines aD, Dc, made specially on account of the present applica- 
tion of the diagram. The circles of simple shading and of shading interrupted 
by two small concentric circles constitute one of the simple cubic assemblages ; 
the unshaded and the circles with shading interrupted by one concentric circle 
