An Improved Level for use in the Construction of Irrigation Works.
Year: 1897

page_text: Date of Application, 2nd Nov., 1897-Accepted, 26th Feb., 1898
COMPLETE SPECIFICATION.
An Improved Level for use in the Construction of Irrigation Works.
I, JOSEPH PIERRE GUIDOUX, Engineer, of Villettes, near St. Just, Haute-Vienne,
in the Republic of France, do hereby declare the nature of this invention, and in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
This invention is composed of a frame formed by two uprights A and A¹ and
two cross pieces C C₁ for keeping the two uprights always parallel. The upright A
is provided at one extremity with a half round tenon O and at the other with a piece
of iron O¹; the upright A is provided at one end with a graduated copper plate B,
and like the upright A with a piece of iron 0%. The two cross pieces C C₁ are
tenoned in A and A', a screw in each tenon enabling the level to be taken apart!
when desired. Two struts D and D¹ serve to keep the frame thus formed true.
The level also comprises a beam E, which is one of the most important parts of
the instrument. It is jointed to the upright A by the tenon 0 and is provided at
its opposite end with a copper plate G which takes into a mortise in the upright A¹
and indicates on the part B the graduation.
The beam is moved by a draw screw H.which engages above B in a threaded
socket and is attached at its lower extremity to the said plate G by a fork, and
which accordingly as it is turned to the left or to the right, raises or lowers the
plate G.
To the cross-piece C are fixed two handles P and P₁; one, P, is immovable, and
the other P, can, by means of two screws p, and holes made for this purpose, be
raised or lowered; these handles serve for the manipulation of the level.
In the centre of the level beam E is placed an air-drop level R, which is the
principal part of the apparatus. It is fixed on the said beam by two pieces of
wood S and S¹, of different sizes. The smaller one S is fixed and the other S¹ is
able to oscillate about its pivot s, in the longitudinal direction of the apparatus.
Each of these pieces has a small cavity for the reception of the ends of the level R
and the oscillating piece S¹ is fixed, after the level is put in position, by means of
a cleat S oscillating about s and in the transverse direction, this cleat engages
with force in the groove s made transversally in the beam E and, in this position,
maintains the piece S¹ vertical.
To disconnect the level R the cleat S" is oscillated out of the groove, then the
piece S¹ is oscillated, which in separating from S, allows the level to be withdiawn.
To the uprights A and A¹ are jointed two feet K K' the lower ends of which may
be separated from the uprights, and, during work, serve to maintain the apparatus
upright. These feet may, for the transport of the apparatus, be fixed to the
uprights A A' by the hooks Z Z¹.
This level is specially adapted for irrigation, but it may be also applied in many
other cases.
The method of using it is one of the most simple and practical. Supposing that
it is desired to give an inclination of 0'02 per metre, with an instrument measuring
we metres, it is sufficient to put the copper bar G on the graduation 004, by means

page_text: The advantages offered by the level above described over the water level are:
1. The suppression of the sighting rod, and thus suppressing the services of one
man.
2. In winter, the time when irrigation works are carried out, no matter how
slightly the wind blows, there is a movement of the water in the tubes, which pre-
vents exact levelling.
3. If the cold is intense the operation becomes impossible unless the water be
replaced by alcohol. The so called irrigation level avoids all these disadvantages.
Furthermore, with the best water levels, and taking points every two metres,
two men can only level 2500 to 2600 metres per day; whilst with the irrigation
level one man can easily level 5000 metres, with the points still taken at two
metres.
.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. The combination of a wooden frame provided with supporting legs, the lower
ends of the frame and the legs being metal shod, with a level-beam E jointed to
the frame at one end and carrying at the other end an indicating plate G sliding in
graduated part B of one of the uprights of the frame; the beam E and the plate G
being able to be brought to the desired degree by means of a screw H.
a
2. The combination of a frame with graduated plate, and a level-beam, above
claimed, with an air-drop level R, supported between two pieces of wood, one of
which S is fixed and the other S' is movable, this latter being able to oscillate in
the longitudinal direction of the apparatus and to be normally held by a cleat S".
3. The combination of a level as above described with a fixed handle and a
handle which may be varied in height.
Dated this 2nd day of November 1897.
WHEATLEY & MACKENZIE,
40, Chancery Lane, London, W.C., Agents.