Year: 1886

page_text: 1, GIOVANNI MANCION, Doctor of Philosophy, of Via S. Andrea delle Fratte
No 12, Rome, Italy, do hereby declare the nature of this invention, and in what
manner the same is to be performed to be particularly described and ascertained
in and by the following statement:-
My invention consists in subjecting the timber to be preserved in a suitable
closed receptacle, first to the action of low pressure steam to swell the wood and
also to create a vacuum for the reception of the solution which I next employ.
This is made in the following proportions:
Arsenic Acid (crystallized) Kilogrammes 0.156
Phenic Acid (commercial) Kilogrammes 3.600
Water
Litres
100°
This solution is then neutralized and rendered alcaline by the addition of a suffi-
cient quantity of potash, and is then introduced into the cylinder, and the wood
subjected to its action for about half an hour under pressure of 10 atmospheres.
This solution is then drawn off and is replaced by a second solution mixed in the
following proportions:
Commercial Sulphate of Iron Kilo.
Water
10.600
Litres 1000.
The timber is subjected to this solution under pressure of twelve atmospheres.
The action is as follows; The arsenic acid and phenic acid combine with the
potash, and kill all germs etc in the wood and arrest decay, only these salts being
soluble would be removed from the wood by water, damp, rain etc. It is therefore
necessary to render them insoluble, which I prefer to do by sulphate of iron, which
combines with the arsenic acid and phenic acid to form arseniate of iron and
phenate of iron releasing the potash which combines with the sulphuric acid of
the sulphate of iron to form sulphate of potash. Some of the iron is reduced to
the form of oxyde and peroxyde of iron, which is also of a value as an antiseptic.
If this however is not required their formation can be obviated by the use of a
larger quantity of Phenic acid in the first solution. When it is found that this
action is completed, as mentioned above, the second solution can be drawn off and
the timber containing the insoluble salts dried in the open air. When perfectly
dry it is ready for use,

page_text: The hydrogen (H) of the hydroxile (OH) contained in the phenic acid (C® H5
OH) can be replaced by a metal. In this instance I have preferred to use iron as
being cheaper, but copper zinc mercury or other suitable metal could be used with
the same result,
The amount of potash added to the first solution must be sufficient to neutralize
not only the arsenic acid and phenic acid, but also the sulphate of iron in the
second solution.
The apparatus necessary is the same as that employed usually for the purpose of
preserving wood, such modifications being introduced as may be necessary for the
working of my process.
The reservoir for the first solution should be made of wood that for the sulphate
of iron may be formed of iron, both these reservoirs should communicate separately
with the preserving cylinder or receptacle.
The quantity of solution is such that about 50 grammes of arsenic acid,
1.280 Kilos of Phenic acid, and 3.498 of sulphate of iron are required for each
cubic metre of wood.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is
1. The preservation of wood by means of the two hereindescribed solutions.
2. The described mode of using the said solutions.
3. The previous steaming of the wood to swell the wood and render it more
capable of receiving the solutions.
4. The substitution for iron in the second solution of any other metal which is
capable of replacing the hydrogen of the hydroxyle of the phenic acid, and so
render the same insoluble.
5. The addition of potash to the first solution in sufficient quantity to neutralize
the arsenic and phenic acids and also the acid in the sulphate of iron subsequently
employed.
6. The application of the said process to wood of all species specially for wood
to be exposed to the action of water air or moisture such as piles, telegraph posts,
railway sleepers, wood pavement and the like.
2000!