holes, Grease-traps, Inspection Openings of Drains, and such like Purposes.
Year: 1886

page_text: Date of Application, 12th May, 1886.
Complete Left, 10th Feb., 1887.
Complete Accepted, 11th Mar., 1887.
holes, Grease-traps, Inspection Openings of Drains, and such
like Purposes.
I, JOHN SMEATON Sanitary Engineer of 56 Great Queen Street London W.C. do
hereby declare the nature of this invention to be as follows:-
I prefer in carrying out my invention to make the frame deeper than usual with a
lute joint or groove to receive a cover or lid with a double rim round same to form
a water or other sealed liquid joint inside the frame above the said air-tight cover or
lid; I fix a second cover or lid allowing a space between same and the air-tight one,
so that if walked or driven over by vehicle or other traffic the inside cover or lid
which hermetically seals the opening is not disturbed, the outside cover or lid pro-
tecting the inside one, in ordinary air-tight covers the joint is invariably broken when
the cover is walked on. prefer also to doubly secure the joint, on the inside of
cover or lid to have a second rim or guard round which I fix a flange or ring of
rubber or other soft material which forms a joint independently of the lute joint
before mentioned, between the two covers or lids a sand joint may be formed or the
space filled up with powdered charcoal or other disinfecting material.
To form a double seal the outside cover or lid may be treated in a similar manner
as the inside one as far as the joint is concerned.
As another important improvement in my Invention and for the better security of
the covers and to avoid them being tampered with I prefer to fix a clip or lock
worked by means of a key or spindle through an air-tight stuffing box either for
single or double covers.

page_text: Improved Air-tight Covers or Lids and Frames suitable for Man-
holes, Grease Traps, Inspection Openings of Drains, and such
like Purposes.
L, JOHN SMEATON, Engineer, of 56 Great Queen Street Lincoln's Inn Fields
London W.C. in the County of Middlesex 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 :-
I prefer, in carrying out my invention, to make the frame deeper than usual, with
a lute joint or groove, to receive a cover or lid with a double rim round same to form
a water, or other liquid sealed joint inside the frame; above the said air-tight cover or
lid I fix a second cover or lid allowing a space between same and the air-tight one, so
that, if walked over by a person or driven over by vehicular or other traffic, the inside
cover or lid which hermetically seals the opening is not disturbed, the outside cover or
lid protecting the inside one; in ordinary air-tight covers the joint is invariably broken
when the cover is walked on. I prefer also to doubly secure the joint, on the inside of
the cover or lid, by having a second rim or guard round which I fix a flange or ring of
rubber or other soft material which forms a joint independently of the lute joint before
mentioned, between the two covers or lids a sand joint may be formed or the space
filled up with powdered charcoal or other disinfecting material. To form a double seal
the outside cover or lid may be treated in a similar manner as the inside one, as far as
the joint is concerned. As another important improvement in my Invention and for the
better security of the covers and to prevent them being tampered with I prefer to fix
a Clip or Lock worked by means of a Key or Spindle through an air-tight Stuffing
Box, which can be applied either to single or double covers.
DESCRIPTION OF DRAWINGS.
Fig. 1 shows a section through improved covers as fixed over cesspools or receivers
of soil, for drainage purposes, the said covers being easily removable for emptying or
cleaning Duct. Figs. 2 and 3 show sections through the cover, as fixed over man-
holes or interceptor traps or drains by the inventor. Fig. 4. shows a view of the
cover complete. Fig. 5 shows the method of securing the under cover by a locking
clip worked through a stuffing box with cap so that the same is air-tight. The cap
covering spindle, as shown, is to prevent the space immediately surrounding the
spindle being filled up with the material used to fill up the space between the covers.
Fig. 6 shows plan of cesspool and inspection manhole ready to receive frame of cover.
Fig. 7 shows interceptor in manhole, plan.
Fig. 8 shows an enlarged section of cover and the methods of securing the air-tight
joints or seals as described in specification, dotted lines at a. show section through

page_text: covers.
lute joint of top cover or lid. b. shows section through the frame supporting lids or
c. shows another form of double lute or trap that may be applied to covers.
e. e. show position of rubber or other washer to make an air-tight joint with frame.
d. d. show the space between the covers or lids to be filled with sand, powdered
charcoal, or other such like substance, or cement of a nature easily renioved for
inspection; either or both of the covers may be hinged. Fig. 9 shows a section
through a frame and double cover with hinged top, lid, or cover, the bottom cover
being secured by my improved locking clip and stuffing box and cap. The object of
the cap is to prevent the space for key being filled up with the material used to fill in
between the two covers. Fig. 10 shows a similar arrangement for interceptor traps
to soil pipes.
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 :
1st. The construction of covers or lids for drains or such like purposes with double
air-tight covers or lids, which may or may not be hinged, and lute or other joint
substantially as shown by the accompanying drawings.
2nd. The method of locking covers so that the cover can be secured by a key
outside and yet be perfectly tight against the escape of gas or fluid, substantially as
shown and described.
3rd. The arrangement of covers to allow of filling, with sand, charcoal, cement, or
disinfecting material, the space between the upper and lower covers.
4th. The top cover to prevent the second cover being interfered with when driven
or walked over.