An Apparatus for the Administration of Anesthetics and other Volatile Vapours.
Year: 1895

page_text: Date of Application, 10th Oct., 1895
Complete Specification Left, 9th July, 1896-Accepted, 26th Sept., 1896
PROVISIONAL SPECIFICATION.
An Apparatus for the Administration of Anesthetics and other
Volatile Vapours.
1, FREDERICK THOMAS GEORGE HOBDAY M.R.C.V.S. Veterinary Surgeon
Royal Veterinary College Camden Town London N.W. do hereby declare the
nature of this invention to be as follows:-
It consists of a bottle having two holes in the cork; one of these admits air, a
valve on the under surface preventing the egress of the vapour in the bottle
through it.
Through the other a tube is passed; to this tube is attached an india rubber
ball containing valves (or an india rubber bellows of 2 balls), which ou being
pressed withdraws the vapour from the bottle by suction & forces it onwards
towards a mask.
This mask is placed on the nostrils of the person or animal for whom the vapour
is intended, the amount of vapour entering the mask being regulated by a
smali tap.
October 10th 1895.
FREDERICK THOMAS GEORGE HOBDAY.
An Apparatus for the Administration of Anæsthetics and other
Volatile Vapours.
I, FREDERICK THOMAS GEORGE HOBDAY, M.R.C.V.S., Veterinary Surgeon,
Royal Veterinary College, Camden Town, London, N.W. 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:-
The objects of this invention are to produce an apparatus for the administration
of anesthetic, and other volatile vapours, whereby the chance of administering
an overdose is greatly decreased, the volatile vapour is only applied where
required, say in the case of an animal, to the nose, the recovery is rapid, and the
chloroform or the like is economically employed.
With these objects in view, I provide a mask of a suitable shape or form according
to the subject of its application, and I connect a tube with the interior of same
having a regulating tap. The tube is connected to an india rubber ball having
valves, or to an ordinary india rubber bellows, in connection, by a tube, with a
bottle containing the anaesthetic; this bottle is provided with a second tube to
admit air but fitted with a valve to prevent egress of the vapour.
The apparatus can be utilized for either human beings or animals according to
the formation of the mask, and in order that my invention may be readily under-
stood I will describe same in conjunction with such a mask, as would be suitable
for small animals, such as dogs, with reference to the accompanying drawings,
whereon similar letters of reference refer to like parts in the several figures.

page_text: Fig. 1 is a general perspective view of the complete apparatus ;
Fig. 2 is a sectional elevation of the bottle (detached) for containing the
auresthetic fluid or other material.
Fig. 3 is an inverted plan view of the cork or stopper showing the tubes and
the valve, and
Fig. is a vertical longitudinal central section of the mask detached:
Figs. 2, 3, and 4 are drawn to a larger scale than is the general view at Fig. 1.
Referring to Fig. 1, A is the bottle or container for the anaesthetic substance,
or other material, having the stopper A' fitted with two tubes B and C. At the
sectional view Fig. 2 it will be observed that the tube B3 passes through the stopper,
and is fitted with a membrane or elastic piece B', see also Fig. 3, attached say at
each end to the cork and stretching across the opening of the tube. This tube B
serves to admit air to the bottle, while the membrane B' acts as a check valve and
prevents the egress of the vapour.
The tube C is connected, as shown at Fig. 1, to an indin rubber or flexible
pipe D, communicating with a flexible ball E, having an inlet valve about E', and
an outlet valve at E. Beyond the ball E is an ordinary elastic reservoir E³, from
which the flexible pipe D extends to a regulating tap F by which the vapour.
enters the mask G.
The mask should be of suitable construction and form to suit the requirements
of the case, that shewn at Figs. 1 and 4 being suitable for small animals such as
dogs. The mask has an outer casing G, an inner lining of absorbent felt or other
suitable material G', removed in part at G to allow of the entry of the tap fitting;
and the ready removal of the absorbent felt or other suitable material G; His
⚫an unstiffened hood of canvas or other suitable material or extension from the
casing G, having an inserted edging cord H', and J is an adjustable collar of
leather or other suitable material connected by Interal straps K and buckles or
other suitable fastening to the said casing G.
The method of application is to secure the animal firmly, in such a way, that
the respiration is not in any way interfered with, apply the mask to the face, and
let an assistant work the bellows.
Apparatus constructed according to this invention, presents the following
advantages, among others: Safety from the chance of administering an over-dose,
as with say fear drachms in the bottle only about one-fifth of a minim of chloroform
vapour well mixed with air would be forced into the mask at each pressure of the
bellows, whilst with oue drachm in the bottle this becomes reduced to one-twelfth
of a minim this can be still further reduced by means of the tap F, and by
pressing the bellows slowly; by only allowing the vapour to come in contact with
the animal's nose there is no rubefacient or irritant effect produced; and recovery
afterwards is rapid, and not attended with any great amount of nausea or
depression. The saving of chloroform is too obvious to need comment. 'As
applied to animals, for a small dog it takes from three to six minutes to produce
complete anaesthesia, and in a large one from five to ten minutes.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, declare that what I
claim is:-
1. An apparatus for the administration of anaesthetics or other volatile vapours,
composed of a bottle for the anesthetic substance or material, a passage or tube
to admit air to the bottle, and a valve therefore to prevent escape of vapour, a
passage or tube from the bottle in connection with a flexible pipe, a pump or elastic
ball and valves to draw vapour, by suction, from the bottle, and deliver it by a
flexible pipe to the interior of a mask of suitable form and construction, all
combined and acting substantially as described.
2. The combination with the apparatus claimed by Claim 1 of the regulating
tap substantially as described.
3. The general arrangement and construction of my new or improved apparatus

page_text: for the administration of anaesthetics and other volatile vapours all combined and
acting as and for the purposes described and illustrated with reference to the
accompanying drawings."
T
1000
BREWER & SON,
London and Leeds, Agents for the Applicant.
BREWER & SON,
London and Leeds, Agents for the Applicant.