1816.] respecting the Nature of Oxymuriatic Acid. 44) 
from the inferior oxides, as these have the oxygen more intimately 
combined ; but is procured only at lower temperatures, and under 
favourable circumstances by the abstraction of the excess of rhodium.* 
The base of rauriatic acid gives, in the same way, first an acid, then 
two super-oxides, then an acid, which can be procured-only under 
favourable circumstances, and by no means directly. 
We have now, J conceive, fully shown that different degrees of 
intimacy subsist between oxygen and the same combustible basis, 
frequently between the same proportions. The combustible body 
in a low temperature often unites less intimately with a greater 
number of atoms of oxygen, and then at a higher temperature 
enters into a closer combination with a smaller number of atoms, 
by which fire is produced, and the excess of oxygen is set at liberty. 
We have seen that this difference in the intimacy of the combina- 
tion takes place, not only between combustible bodies and oxygen, 
but likewise between other bodies, both simple and compound, as 
is evident from the experiments on the production of sulphuret of 
platinum by the moist way, on the metalline antimeniates and the - 
siliciate of yttria. This more intimate union, then, is a general 
appearance, and it cannot be alleged that it has been contrived 
merely for the purpose of accounting for the explosion of euchlorine. 
it is evident, therefore, that the explanation furnished by the old 
doctrine agrees fully with every other department of chemical 
science. 
(To be continued.) 
ARTICLE V. 
Trigonometrical Survey of the Wide Mouth Shoal, or Royal Sove- 
reign’s Shoal, near Beachy Head, in the English Channel. By 
Col. M. Beaufoy. 
[For the Diagram see Plate L. Fig. J, c.] 
OssERVATIONS made with a Hadley’s sextant for determining the 
situation of the Wide Mouth Shoal, or the place on which some 
years past the Royal Sovereign man of war grounded, and was 
nearly lost, and which shoal is in a book of pilotage denied to exist. 
Triangle, I, B, H. 
H, Q,B, 25°57’ 20” I, B, 71,901 feet. 
Observed f ‘ Given f H, B, 48,290 
B, Q, 1, 62 38 25 
angles.. Uy, Q,s, 21 26 20 J, B, H, 55° 59° 58” 
* See my treatise On the Cause of Chemical Proportions, Annals of Philesophy, 
vol. iii, p, 255. 
Vou. VIL, N° VI. 9F 
