26 REPORT—1857. 
recorded by interchanging the observers at these stations, the nstruments remaining 
unchanged, and by various mechanical improvements in the recording apparatus of 
the telegraph, chiefly with a view to ensure uniformity of motion in the slips on 
which the recording dots were impressed, he showed that a degree of accuracy 
hitherto not approached by any other method had been obtained,—the error of both 
clocks disappearing also in the results, if only their rates had been made perfect. 
On a Proposal for the Establishment of a Uniform Reckoning of Time in 
connexion with the Telegraph. By J.J. Murruy. 
The author said, that as in Britain the establishment of the telegraph had made 
it necessary to adopt Greenwich time all over the country, where the difference was 
small this was possible, but when the telegraph extended to America, or greater 
distances, it would cease to be so. He proposed that all clocks should be furnished 
with a double circle of figures on the dial, the outer circle being moveable through 
any required number of degrees. When aclock is set up at any place, let the hands 
show local time on the inner circle; and let the outer circle beso set, that the hour- 
hand will on it show Greenwich time. 
On some Phenomena in connexion with Molten Substances. 
By J. Nasmytu, F.R.A.S. 
The author stated, on introducing the above subject to the notice of the Section, 
that his object in so doing was to direct the attention of scientific men to a class of 
phenomena, which although in their main features they might be familiar to practical 
men, yet appeared to have escaped the attention of those who were more engaged 
in scientific research. The great fact which he desired to call attention to is com- 
prised in the following general proposition, namely, that all substances in a molten 
condition are specifically heavier than the same substance in an unmolten state. 
Hitherto water has been supposed to be a singular and special exception to the ordi- 
nary law, namely, that as substances were elevated in temperature they became 
specifically lighter, that is to say, water at temperature 32° on being heated does on 
its progress towards temperature 40° become more dense and specifically heavier 
until it reaches 40°, after which, if we continue to elevate the temperature, its den- 
sity progressively decreases. From the facts which Mr. Nasmyth brought forward, 
it appears that water is not a special and singular exception in this respect, but 
that, on the contrary, the phenomenon in relation to change of density (when near 
the point of solidification) is shared with every substance with which we are at all 
familiar in a molten state, so entirely so, that Mr. Nasmyth felt himself warranted 
in propounding, as a general law, the one before stated, namely, that in every in- 
stance in which he has tested its existence, he finds that a moltemsubstance is more 
dense, or specifically heavier, than the same substance in its unmolten state. It is 
on account of this, that if we throw a piece of solid lead into a pot of melted lead, 
the solid, or unmolten metal, will float in the fluid, or molten metal. Mr. Nasmyth 
stated, that he found that this fact of the floating of the unmolten substance in the 
molten, holds true with every substance on which he has tested the existence of the 
phenomenon in question; as, for instance, in the case of lead, silver, copper, iron, 
zinc, tin, antimony, bismuth, glass, pitch, rosin, wax, tallow, &c.; and that the 
same is the case with respect to alloys of metals and mixtures of any of the above- 
named substances: also, that the normal condition as to density is resumed in 
most substances a little on the molten side of solidification, and in a few cases the 
resumption of the normal condition occurs during the act of solidification. He also 
stated, that, from experiments which he had made, he had reason to believe that by 
heating molten metals up to a temperature far beyond their melting-point, the point 
' of maximum density was, as in the case of water, at 40° about to be passed; and 
that at such very elevated temperatures, the normal state, as regards reduction of 
density by increase of temperature, was also resumed, but that as yet he has not 
been able to test this point with such certainty as to warrant him to allude further 
to its existence. 
Mr. Nasmyth concluded his observations by stating, that he considered this to be’ 
a subject well-worthy of the attention of geologists, who might find in it a key to 
