52 On Subdivision by Trituration and Solution. 
in the ratio of one hundred to one; and a grain of the thirtieth 
trituration of gold would contain as many minute pieces as agrain 
of the third trituration 
But I am eonvineed that the intensity of some properties of 
substances is greatly increased by comminution. If the sphere of 
cohesion is thus increased, the maximum comminution will fall 
below the above estimate. I believe that in practice the commi- 
nution will fall below it, not only for the above reason, but also 
because the trituration, though continued sufficiently long to 
bring most of the parts to the maximum size, will be Sine-cximecanm 
before every part 1s equally reduced. 
enee microscopic observations are liable to lead to erroneous 
conclusions. Dr. Mayerhofer has seen scores of millions of pieces 
of metal in a single grain of the sugar with which it had been 
triturated to form the third trituration.. The number varied with 
different metals. From the considerations which I have above 
stated, as well as from others, | am convinced that the number of 
invisible pieces far exceeded the number of visible ones. Those 
only were seen ated had escaped the full effect of the dividing 
forces. 'The minimum groups in the third trituration are not o 
jects of ietonetini vision. From the wide range of magnitude 
in the visible pieces, as well as from the appearance, on close in- 
spection, of pieces at first invisible, Dr. M. justly concluded, that 
in the first trituration of precipitated gold, ‘the metal is divided 
into particles so small as to be invisible under a glass magnifying. 
14,000 times.’””. He “examined the fourth trituration by a power 
magnifying 90,000 times, and it was evident that the diminution 
of the particles progressively increased ; the smallest gold mole- 
cules appeared yellow, and the metallic lustre was not to be mis- 
e The diminution here refers to the visible ones. As the 
conclusions which I have drawn in regard to the facility of re- 
union, the limit of comminution, and the intensity of properties, 
refer to those more numero us groups which are so small as to be 
invisible by the most powerful microscope, it would be impossi-— 
ble either to establish or refute them by microscopic observations. | 
The above method of trituration has great advantages for 
effecting a minute division of substances. 1 have shown, that in 
order to triturate a substanee to powder of a certain of 
ie fnaners, it is necessary to mix it with a sufficient quantity of - 
er substance ; and that the requisite quantity of this ad- 
misture increases with the fineness required. a de of 
ess can be specified, as would render the labor of eomminu- 
ting aeuincie. grain impracticable, even ifthe requisite amount: 
the admixture could be obtained. The labor of the 
whole h race operating through all ages since the creation’ 
of man, cout not agent triturate a — grain of one sub- 
stance w grains of any other substance. Yet the 
