S98 Scientific Intelligence. 
one-third of A, and which has one-third of the number of teeth* 
An index fastened to the axis of the small wheel a r indicates the 
temperature of a circular scale, which is divided into 360°. In- 
stead of passing the platinum-wire round the axle of the wheel 
A, it has been found better in practice, to attach a short silken 
thread to its extremity, and pass that round, and fix it to the 
spring.— See Journal of Science , &c. vol. xi. p. 309- 
15. Results obtained by Mr DanielVs New Pyrometer . — -The 
experiments by which the following results were obtained, were 
repeated more than once, with a very close agreement of results. 
The fusing point of silver is most to be relied upon, as Mr Da- 
niell obtained it by three different trials, all within a degree of 
one another. 
Daniell’s Scale. 
Boiling point of Mercury, 92° 
F using point of Tin, - - 63 
, ^ - — — Bismuth, - 66 
— Lead, - - 87 
■ — Zinc, - • 94 
— — — — Brass, - - 267 
— — — — — Pure Silver, - 319 
— Copper, - - 364 
— Gold, - - 370 
— — Cast Iron, - 497 
Red heat, just visible in day-light, 140 
Heat of a common parlour-fire, 163 
Fahr. Thermo- 
Wedge wood' 
meter. 
results. 
644° 
600* 
441 
462 
609 
648 
1869 
3807 
2233 
4717 
2548 
4587 
2590 
5237 
3479 
17977 
980 
1077 
1141 
The difference between these results and those obtained by 
Mr Wedge wood, appears from the last column of the pre- 
ceding table. Mr Daniell terminates his paper with the two 
following facts : ls£, That mercury amalgamates readily with 
platinum at about its boiling temperature. When the mercury 
is volatilised by a strong red heat, the platinum is left in a 
honeycomb or dissected state. 2d, A piece of cast iron, strong- 
ly heated, and then cooled slowly in a muffle, becomes covered 
with small, but very distinct, octohedral and tetrahedral crystals, 
and black oxide of iron. The facets of the crystals were very 
perfect and brilliant ,— Journal of Science , vol. xi. p. 317. 
