38 REPORT—1849. 
tinuing for a whole year every week this analysis of the water which is used to pro- 
vide Copenhagen, observed the following facts :— 
1. The quantity of organic matter is greatest in summer. 
2. It disappears, for the most part, as soon as the water freezes. 
3. Its quantity is diminished by rain. 
4, Its quantity is diminished if the water has to run a long way in open channels. 
On the Compounds of the Halogens with Phosphorus. 
By J. H. Guapstong, Ph.D. 
It is well known that chlorine, bromine, and iodine will combine directly with 
phosphorus, yielding compounds containing three atoms of the halogen. Cyanogen 
does not so combine. Ifa larger amount of the halogen be employed, compounds 
are formed containing five atoms. All these substances are neither basic nor acid ; 
they are resolved by water into the hydracids of the halogens, and phosphorous or 
phosphoric acid. If phosphorus be distilled with chloride, bromide, or iodide of mer- 
cury, the ter-compound results. There exists a ter-fluoride (Davy). The ter-cya- 
nide is doubtful. 
The penta-compounds of the halogens with phosphorus may easily be reduced to 
the ter-compounds, The addition of fresh phosphorus will effect this in each instance. 
Phosphuretted hydrogen has already been observed to reduce the pentachloride; it 
has the same effect upon the pentabromide. Hydrogen alone has no reducing power 
upon either of these compounds. Heat alone however will effect the reduction of 
the pentabromide; if a current of dry air be passed over it at 212° F., so as to re- 
move the free bromine, pure terbromide is obtained. The higher compound of iodine 
and phosphorus may be similarly decomposed, but not the pentachloride. 
The force of affinity for phosphorus is in the order—chlorine, bromine, iodine, The 
ter-compounds are not directly acted upon by oxygen or sulphur, but suffer double 
decomposition by water or hydrosulphuric acid. The comparative feebleness with 
which the two additional atoms of the penta-compounds are combined, is also evident 
from the action of certain non-metallic elements; thus, iodine reduces the pentabro- 
mide of phosphorus. The moderated action of water upon the pentachloride forms an 
oxychloride of phosphorus (Wurtz), and there exists an oxybromide of phosphorus, 
PBr, O., exactly analogous. No compound, similar to the sulphochloride of phos- 
phorus ef Serullas, is formed by the action of hydrosulphuric acid on the pentabro- 
mide, but a liquid, the analysis of which appears to suggest the composition 3PBr, 
+PS,;. No such compounds exist in the iodine series. 
The increased stability, which the substitution of two atoms of oxygen, or sulphur, 
for two atoms of the halogen, imparts to the remaining three atoms, is manifest from 
—1, the non-action of hydrosulphuric acid; 2nd, the fact that metals, even potas- 
sium, are not attacked by them; 3rd, the non-action of phosphorus. 
Hydrochloric acid produces no partial double decomposition with the pentabromide 
or pentiodide. Nor does any halogen combine directly with the ter-compound of 
another with phosphorus. If bromine and iodine be presented simultaneously to 
the terchloride, pentabromide of phosphorus is formed. A colourless crystalline body 
exists, belonging to the bromine series, never obtained in quantity, possibly isomeric 
with the oxybromide. 
Sulphur appears to combine directly with pentachloride of phosphorus when they 
are fused together; a crystalline body, and a straw-coloured liquid result. The 
analysis of these compounds is attended with peculiar difficulty, nor had the author 
sufficient time to investigate all the anomalies of their decomposition. The straw- 
coloured liquid however would appear, to be P Cl; S,. The provisional name of Sul- 
phurets of the Pentachloride of Phosphorus is given. 

On a continued spontaneous Evolution of Gas at the Village of Charlemont, 
Staffordshire. By Samurt Howarp. 
In a field by the side of a lane, near the village of Charlemont in Staffordshire, 
certain patches of ground had been noticed, which, without any apparent cause, were 
destitute of vegetation. They excited little attention, as they were supposed to be 

