SCIENTIFIC SUMMARY. 
383 
definite and indivisible atoms ; but they carry the mind down towards the 
infinitely small until it is lost and bewildered in figures and quantities 
overwhelming in their minuteness, in the same manner that a contempla- 
tion of astronomical magnitudes transcends human comprehension in their 
almost infinite vastness. The illustration is derived from well-known 
properties of the metal gold. A sheet of gold leaf in its ordinary form has 
a thickness of about the ^v^-cnro-th of an inch, and weighs the -^th of a 
grain per square inch. If one of these leaves be caused to adhere to a 
plate of glass (by breathing on the latter, and placing it on the gold), and 
a very dilute solution of cyanide of potassium be applied at the edge of the 
leaf, it will pass between the glass and the gold, and the latter will be 
perfectly stretched out, and floated on the saline solution. The solvent 
powers of the cyanide of potassium will now exert themselves ; the gold 
will be gradually dissolved away, becoming thinner and thinner until a 
film of almost any desired degree of attenuation is left. At any moment 
the process may be stopped by washing away the cyanide by water ; if 
then alcohol be used, and finally alcohol containing a minute portion of 
varnish, the gold film may be obtained, cemented to the glass plate. This 
method of reducing the thickness of gold-leaf we owe to Faraday ; by its 
means the thickness will have become reduced to about one-twelfth part 
of what it was originally, weighing (in round numbers) the -s-Ao-th of 
a grain to the square inch, and having a thickness of only about the 
-ssTnrvj-irmrth of an inch. In this state the film presents none of the 
ordinary appearances of the metal, being perfectly transparent and re- 
sembling a delicate film of pale green varnish, more than a dense metallic 
substance. Chemistry having given us this near approximation to a 
mathematical surface, how far can it be subdivided mechanically? By 
subdividing this surface after the manner of Robert, whose test lines are well 
known to microscopists, a small grain of gold — a fragment scarcely larger 
than a pin’s head— has thus been divided into three billion, eight hundred 
and forty thousand million separate pieces, each one of which is capable of 
being distinguished under the microscope ! In order to enable our readers 
to form some faint idea of the significance of such overwhelming figures 
as these, we may state that the proportion which each square bears to the 
original grain of gold is about the same that a thimble does to a building 
five times the size of St. Paul’s. 
The difficult subject of chemical nomenclature, so formidable a 
stumbling block in the path of students, has been attacked by Mr. 
J. A. R. Newlands, who proposes the adoption of a 1 system of building 
up the names of organic bodies, whereby the exact formula of any sub- 
stance can be told from the arrangement and position of the letters 
and syllables of the word. The result of Mr. Newland’s system is that 
Hoffmann’s celebrated substance, Methylethylamylophenylammonium, 
will find itself transformed into Bafyldahylliarylkahylammonium ; no great 
advantage as far as length or pronounceability is concerned, but being 
useful, inasmuch as its name represents the mode of arrangement of its 
elements, as well as its formula and exact composition. The insuperable 
objection to this and all other attempts to remodel chemical nomenclature 
is, that they are simply incapable of being introduced. If chemists would 
