SOO .Mr Herschel’s Process for Separating Iron from: Metals. 
trance of servants, to trim the lamp instead of having the fui’- 
niture destroyed by the spilling of oil, and by ‘the carbonaeeotus 
matter necessarily produced by either oil or wax burning with- 
in an apartment ; — instead of having the temperature of over- 
heated rooms increased bv the heat of the lights ; — instead of 
having the eye injured by the irritation which arises from bril- 
liant flame ; — and instead of having the apartment illuminated 
by a light constantly varying in intensity, we shall avoid all 
these evils, and have our houses lighted in the very same man- 
ner as they are by the light of day. 
The disadvantages which attend this method are very few. 
We are prevented from excluding the cold air of winter by 
shutters and curtains; but in many cases this is an advantage, 
and when it is not desirable, the lieat on the outside of each 
window will diminish the currents of cold air which might other- 
wise be admitted. A greater quantity of light wilt no doubt be 
necessary to produce the same degree of illumination ; but tlie 
cheapness of gas renders such an objection of no weight. 
The gas-light might also be established in the stone-ym\h of 
apartments, by means of gas and air pipes laid in the walls them- 
selves, so that the air in the room should be entirely unconnect- 
ed with that which supports the flame of the gas. 
13. Account (f a New Process for separating Iron from otJier 
Metals. By J, F. W. Herschel, Esq. F. R. S. L. & E. ^ 
The following process, discovered by Mr Herschel, is of great 
value in the arts, from its being mathematically rigorous, — of ge- 
neral application, and having the advantage of facility, celerity, 
and cheapness. 
The solution containing iron is to be brouglU to the maxi- 
mum of oxidation, which can be communicated to it, by boiling 
with nitric acid. It is then to be just neutralised, while in a 
state (f ebullition.^ by carbonate of ammonia. The \\Eole of the 
iron to the last atom is precipitated, and the wliole of the other 
metals present (which I suppose to be manganese, urium, nickel 
and cobalt,) remain in solution. 
From the PUl. rra/j^. 1821, p. 293. 
