IMPROVEMENTS IN DREDGING, EXCAVATING, AND ELEVATING MACHINERY
Year: 1873

page_text: LETTERS PATENT to Simon Robertson, of the City of Glasgow, in
the County of Lanark, North Britain, Civil Engineer, for the
Invention of "IMPROVEMENTS IN DREDGING, EXCAVATING, AND ELEVATING
MACHINERY."
Scaled the 30th January 1874, and dated the 18th August 1878.
PROVISIONAL SPECIFICATION left by the said Simon Robertson at the
Office of the Commissioners of Patents, with his Petition, on the
18th August 1878.
I, SIMON ROBERTSON, of the City of Glasgow, in the County of Lanark,
North Britain, Civil Engineer, do hereby declare the nature of the said
Invention for "IMPROVEMENTS IN DREDGING, EXCAVATING, AND ELEVATING
MACHINERY," to be as follows, that is to say:-
This said Invention has reference to a new or improved construction
and arrangement of the parts of chain buckets and their gear, particularly
suitable for excavating, dredging, and elevating and discharging the

page_text: sand, clay, stones, or other earth from the centre and bottom of the
brick, iron, or other cylinders, while and for sinking them for making
the foundations of quays, docks, bridges, and other structures, which
improvements are also applicable for other excavating, dredging, or
elevating purposes, as for the loading and discharging of grain and salt, !
or other such cargo in bulk, or ballast, such as sand, gravel, or small
stones from ships and vessels, all in a more simple, efficient, and
economical manner than has heretofore been effected by such machinery.
And the nature and novelty of this Invention as applied to excavating
or dredging and removing the sand or earth out of the centre of a set of :
three or more of the said cylinders while being sunk for foundations,
which will be sufficient to make the same understood for the other
purposes stated also consists all as follows:-In this application, the
driving horizontal shaft would be carried in bearing brackets secured
high up above the top of the cylinders, and considerably to one side, as
to the uprights of one side of the framing of the overhead travelling
crane, for lifting and laying down the lengths or sectional parts of the
cylinder as they are to be sunk, with a square or other polygonal
working or lifting barrel for each endless chain of buckets to pass over
and be turned by, and in a transverse line with or from each cylinder,so
that the two lines of each chain of buckets after passing at a considerable
angle downwards from the driving barrel would pass over guide barrels
carried on spindles, the journals of which would work in bearing bushes
in a cast-iron or strong wood framing erected over each cylinder, into
which the long loose loop of the chain of buckets would hang, so as to
work into the earth at the bottom to be excavated and raised with a
triangular, square, or other polygonal heavy metallic barrel or block,
revolving loose within the loop of the chain, to assist in forcing and
tilting each lower bucket as it came to the bottom into and through the
earth, so as to fill them for their upward traverse over the outer and
upper guide and carrying barrel at the top of the cylinder, and onwards
up the incline, over the upper or drawing barrel, over which they would
be emptied into an angular shoot into the trucks or waggons on the line
of rails outside the said supporting or travelling crane frame, from which
upper barrel the chain would come down in a loose hanging curve
towards the lower near reversing and guiding barrel over the cylinder,
and which would be large and hollow to give sufficient room for the
inverted buckets to cuter without touching the spindle or shaft, the
"

page_text: chains resting on polygonal flanges projecting from each end disc or side
centres of the barrel.
The buckets are fixed on every alternnate or other set of links formed
by two side links, but the intermediate or other set of links between the
buckets might be formed of four or more links attached to the bucket
links by long joint pins or bolts fixed by end nuts or cotters. These
several intermediate or other sets of links have a strong raking or pick-
shaped pike formed or fixed on each, receding preferably to or from
each side link towards the centre in the form of the letter A or V, each
pike projecting in advance of the other as high or a little higher than
the buckets, to break up and loosen the earth and stones, so that the
buckets will fill easier, and when stones occur too large to be carried up
by the buckets, the set of V shaped picks will bring up these.
The spindles of the guiding barrels over the cylinders or part where
the vertical loose chain of buckets is reversed away laterally at an angle,
are preferred to be geared direct, either by toothed or friction wheels, so
that the one barrel will lower at the same speed as the other is rising, by
the pulling strain upon it, while the compensation required for the
lowering of the loose loop of chain within the cylinder, or the effect of
the lowering of the cylinder as it sinks by the excavating of the earth
from under it, through the slacking of the return hanging chain of
bucket between the driving delivery barrel and the hollow guiding
barrel, is effected or given by the letting off less or more of this slack, as
desired, by coupling these wheels, so that they can be shifted a few teeth
or short distance, in relation to each other, or in relation to that of their
barrels by a friction clutch, or by shifting the wheel into gear with a
pinion and crank handle, which could so shift and turn the wheels, and
give off the chain at the same time, without slipping or letting go the-
slack of the chain of buckets in either direction more than was required
to suit the proper working of the buckets and rakes below, and as the
depth increases new intermediate links and buckets can be added to
lengthen the endless chain.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Simon Robertson in the Great Scal Patent Office
on the 12th February 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, SIMON
ROBERTSON, of the City of Glasgow, in the County of Lanark, North
Britian, Civil Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Thirteenth day of August, in the year of
our Lord One thousand eight hundred and seventy-three, in the thirty-
seventh year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto me, the said Simon Robertson, Her special licence
that I, the said Simon Robertson, my executors, administrators, and
assigns, or such others as I, the said Simon Robertson, my executors,
administrators, and assigns, should at any time agree with, and no
others, from time to time and at all times thereafter during the term
therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVEMENTS
IN DREDGING, EXCAVATING, AND ELEVATING MACHINERY," upon the condition
(amongst others) that I, the said Simon Robertson, my executors or a
administrators, by an instrument in writing under my, or their, or
one of their hands and seals, should particularly describe and ascertain
the nature of the said Invention, and in what manner the same was
to be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that I, the said Simon Robertson, do hereby declare
the nature of my said Invention, and in what manner the same is to be
performed, to be particularly described and ascertained in and by the
following statement in writing, reference being had to the accompanying
Sheet of Drawings, and to the letters and figures marked thereon, that is
to say :-
My said Invention has reference to a new or improved construction
and arrangement of the parts of a chain of buckets and their gear (or
connecting, carrying, and working mechanism) particularly suitable for
excavating, dredging, and clevating and discharging the sand, clay,

page_text: stones, or other earth from the centre and bottom of the brick, iron, or
other cylinders, while and for sinking them for making the foundations
of quays, docks, bridges, and other structures, which improvements are
also applicable for other excavating and elevating purposes, as dredging
from the bottoms of rivers and other places, or for the loading and dis-
charging of grain and salt or other such cargo in bulk or ballast (such as
sand, gravel, or small stones) from ships and vessels all in a more simple,
efficient, and economical manner than has heretofore been effected by
such machinery.
And in order that my said Invention, and the manner of performing
the-same may be properly understood, I shall now proceed to describe
the several Figures on the explanatory Sheet of Drawings which I have
hereunto appended, for the purpose of showing what I at present believe
to be the best modifications and arrangements for carrying it into effect
or practice, the same reference letters indicating the same or like parts
in all the Figures where shown.
---
Figures 1 and 2 are a sectional elevation and a plan respectively, the
former taken on the sectional line 1 - 1 in Figure 2 of a modification
or arrangement of my said improved excavating machinery or mechanism
carried on a strong self-contained frame C, C¹, crected over and applied
for the sinking of a set of three-brick cemented cylinders for foundations,
and so that weights W for sinking the cylinders may be laid on the
framing over the whole.
Figure 3 is a sectional elevation of another modification or arrange-
ment of my improved mechanism as applied to a portable or carriage
frame Cu, C³, carrying its driving engine Y and my said improved
machinery for traversing on rails a, or other equivalent portable road-
way z³, for excavating deep cuttings below, and removing and carrying
the excavated material some considerable distance laterally, and depositing
it in waggons for removal.
Figure 4 is a side elevation of a modification or arrangement of my
said improved excavating machinery O, O³, erected on a swivelling
frame C, C, carrying its driving engine and machinery upon a turn-
table L, II, and portable carriage C", O³, traversing on rails & or other
roadway at the bottom of the " cutting," for excavating" cuttings"
above the said roadway a³, and removing the excavated material into
waggons M behind or laterally at one or both sides of it,

page_text: Figure 5 is a side elevation of another modification or arrangement of
my said improved excavating machinery C, C³, erected on a portable
carriage O¹¹, C³, carrying its driving engine and machinery, and traversing
on rails x or other portable roadway, for cutting trenches Z, and removing
the excavated material to the sides or behind it.
And Figures 6, 7, and 8 are views of my new excavating machine C, C³,
and lowering chain barrel e, E, essential and peculiar to my improve-
ments, drawn to a large scale to show its construction more clearly than
in the general arrangements, Figures 1 to 5.
Referring to Figures 1 and 2, the nature and novelty of my said
Invention, specially as applied to excavating or dredging and removing
the sand, earth, and small stones out of the centre of a set of three (or it
might be other number), of the said cylinders Z while being sunk for
foundations (and which I believe will be sufficient to make the nature
and mode of performing the Invention understood, also for the other
purposes stated) consist all as follows:-In this application Figures 1
and 2, the first driving horizontal shaft, as A or A¹ of the improved
mechanism, the latter indicated in red lines in Figure 1; might be carried
in bearing brackets secured high up above and considerably to the one
side of the top of the cylinder Z being sunk, such as to the uprights
of one side of the framing of the overhead travelling crane for lifting
and laying down the lengths or sectional parts of the cylinder Z as they
are to be sunk, or it may be the main framing, as C, C¹, carrying the
chain, raising and lowering barrels, and actuating gearing. This shaft A
or A³, which may be driven by any adjacent prime moving shaft or
engine for the purpose, has a square or other polygonal working and
lifting barrel B or B¹ for each endless chain of buckets a, a, b, to pass
over and be returned by, and carried in a transverse direction to the line
of chains with or from the top of each cylinder or set of cylinders, so that
the two lines of each chain of buckets, after passing laterally or at a
considerable angle downwards from the driving barrel B or B', would
pass over guide barrels D, E, carried on spindles d, e, the journals of
which would work in bearings or pillow blocks carried in the cast-iron
side frames C, C³, or it might be other strong wood framing erected over
each hole being excavated, and cylinders being sunk, into which each
long loose loop of the chain of buckets a, a, b, would hang, so as to
work into the earth at the bottom Z¹ to be excavated and raised, either
with or without a triangular, square, or other polygonal heavy metallic

page_text: barrel or block o revolving loosely within the loop of chain to assist in
forcing and tilting each lower bucket 6 as it comes to the bottom into
and through the earth, so as to fill them in succession for their upward
traverse over the outer and upper guide and carrying barrel D, d, at the
top of the cylinder, and onwards laterally or up the incline over the
upper or drawing barrel B or B³, over which they might be emptied on
to an angular shoot ³ into the trucks or waggons on the line of rails
outside their supporting frame, or otherwise emptied into a lateral
endless chain carrier Fª carried over the chain barrels f¹, F. From the
said upper barrel, as B, A, shown in red lines in Figure 1, when at a
considerable lateral distance from the cylinders, each chain a³, b, would
be reversed and led down and back in a loose hanging curve a* towards
the near reversing and lowering guide barrel E, e, and over it down into
each hollow cylinder E below to complete the circuit. This near lowering
chain guiding barrel E, e, would be large and hollow to give sufficient
room for the inverted buckets b to enter without touching the chain
carrying and lowering bars E' and spindle or shaft e, passing through
the side discs E, the chains resting on these bars E¹ (or it might be on
polygonal flanges projecting from each end disc or side centres), all
firmly bolted and secured together to form the barrel E, e, and as shown
more particularly in the large detached scale views, Figures 6 to 8.
The buckets bare preferably fixed on every alternate or other set of
links a, a², formed by two inner side links a, a, but the intermediate or
other set of links a³, a¹, between the buckets might be formed of four or
more links a¹, a¹, attached to the bucket links a, a, by long joint pins or
bolts a³, fixed by end nuts a", or it may be cotters. These several inter-
mediate or other sets of links a', a³, may have a strong raking or pick-
shaped pike a³, formed or fixed on each, receding preferably from each
side link towards the centre, in the form of an obtuse V; and these
pikes a, so placed in advance of each other, project as high, or a little
higher than the buckets 6, to break up and loosen the earth and stones
so that the buckets will fill more easily; and when stones occur too
large to be carried up by the buckets b, the V ranged set of pikes a³ will
bring up these.
The spindles d, e, of the guiding barrels D, E, over the cylinder Z or
part where the vertical loose chain of buckets.a, a³, b, is reversed away
laterally at an angle, are preferred to be geared direct, either by toothed
or friction wheels G, G³, (indicated by red lines in the elevational

page_text: Figures) so that the one barrel E, e, will lower the descending side of
the chain of buckets a, b, at the same speed as the other barrel D, d, is
drawing or raising the other ascending side of the chain by the pulling
strain upon it.
The compensation required for the lowering of the loose loop of chain
at c within the cylinder, or the effect of the lowering of the cylinder as
it sinks by the excavating of the earth from under it, is given through
the slack of the return or loose hanging curve part a* of the chain of
buckets a, a¹, b, between the driving or reversing barrel B, and the
hollow lowering guiding barrel E, by the lifting of less or more of this
slack a* as desired; by coupling these wheels G, G³, so that they can
be shifted a few teeth or short distance in relation to each other, or in
relation to that of their barrels D, E, by a friction clutch or other
equivalent, as by shifting the wheel G or G¹ into gear with a pinion
and crank handle, which could so shift and turn the wheels G, G¹, and
give off the chain at the same time without slipping or letting go tho
slack of the chain buckets in either direction more than was required to
suit the proper working of the buckets and rakes as below; and as the
depth increases new intermediate links a or a¹ and buckets 6 can be
added to lengthen the endless chain a, a¹, b.
The main side frames C, C, carrying the working barrels B, D, E,
and mechanism are bolted together by transverse stays C¹ and set down
or secured to beams or a wooden frame z on top of the set of three
cylinders Z being sunk. The motive-power engine Y may be carried
thereon also at each side or have their cylinders secured on to each side
frame C, having the connecting rods driving the motive shaft H as the
crank shaft passing right across the machine, or it might be a shaft I
giving motion to this shaft H by the pinion and large wheels I', I", as
an intermediate shaft to actuate the shaft A of the drawing and reversing
chain barrels B through the sets of pinions and wheels H¹, H", at their
sides.
The loose barrel c at the bottom loop of the chain is shown in Figure 1
as a heavy triangular, or it might be either polygonal block, with its
sides nearly equal to the length of the links a, a³, and have side flanges
to maintain it in position within the lower loop of the excavating end of
the chain of buckets b, so as to assist in turning over and forcing them
into the earth to be excavated at Z'; but it is to be understood that

page_text: this barrel c might be formed with a central spindle and transverse
chain bearing bars c³, c", indicated in dotted lines in Figure 1 (or with
these bars only without the central spindle having their rolling poly-
gonal weight inside of these, as shown in the lower barrel c, Figure 3),
and when so made this barrel might be carried in journal bearings at
the lower end of a frame or ladder, supported from the top between the
ascending and descending chain of buckets a, b, as shown in the other
Figures, 3 to 5.
-
It will be observed that the main strong side frames C, C³, carrying
the whole are bolted together laterally by the cross stays or tie bars O¹
on each side of the raising and lowering chain drums or barrels D, d, E, e,
the two adjacent ones of the side sets being placed at such a distance
from each other that a third set of frames O*, C*, are bolted to their
front ends with transverse stays O¹, all so as to form the frames of the
third set of raising and lowering barrels D, d, E, e, over and for the
excavating chain of buckets a, b (of the front or third cylinder Z),
having their top lateral delivery scoop brought back over a central
driving barrel B or B¹ in the centre of the shaft A or A³, the latter,
shown in red in Figure 1, so as to deliver the excavated material
from the whole three cylinders Z and sets of chain buckets a, b, either
high up at ¹ into waggons or into the three sets of chain carriers F, F,
for the special purpose of carrying the material to any desired distance and
height to deposit it in waggons or otherwise to suit suit circumstances;
and in this latter case the three main frames 0, 0, 0³, are made of
3 such a height as to have the heavy weights placed on them, above the
cylinders Z, and all the actuating barrels and lateral lines or chains of
buckets, while and so that both the excavating below and the sinking of
the cylinder Z may go continuously on at the same time.
Referring to Figures 6 and 7, which show a sectional elevation and a
› front elevation of the upper driving barrels A¹, B³, D, d, E, e, and J, j,
all geared together for actuating their chain of buckets a, a, b, around
them at the top (as indicated by red lines and arrows in Figures 1 to 6),
the latter conducting one J, j, being fitted at top of the ladder frame K,
when that is used, so that it is carried by and oscillates on its spindle j.
5 These detached views show the details of construction and arrangement
of the parts as well as Figure 8, which is a plan detached of the new or
improved large hollow barrel E, e (to show its construction also), for the
inverted buckets 6 to enter at the bend and return of their chains a, a¹³,

page_text: down to their lower reversing barrel c, c, either carried in the lower end
of the ladder K or in the loose loop of the chain of buckets a, b, as
before described, where the action and excavation of the earth begin.
This hollow barrel E, e, is formed of the side discs E firmly bolted
together by the ends of their chain bearing bars E¹ and nuts E³ outside,
the whole, being firmly keyed on their spindle e by strong eyes on the
inside of the discs. The bearing bars have projections or hook pieces E"
at intervals between the links a, a', of the chains to catch and hold on
the long cross bolts as passed through their connected ends to form the
joints and endless chain a, a¹. The buckets 6 are preferred to have a
narrow part near the inner alternate pair of links a, to which they are
rivetted on each side, and have their outer part 6¹ projecting laterally
considerably over the chain a, a¹, and flanges of the small driving and
carrying barrels A, D, which guide the chains, so that their front and
mouth part 6¹ excavates a hole somewhat wider than the lower carrying 1
barrel c and its carrying ladder K when that is employed. The other
set of alternate pairs of links a' are jointed outside of those attached to
the buckets by long joint pins a³ passing right across, as before referred
to, for being caught by the carrying bars E¹, E", the tumblers, and are
fixed at their ends by a screw nut a¹¹, at one or both ends, or other :
equivalent fastening; and at the parts where the raking or grappling
points a³ are desired to be placed these links are made in a set of five,
seven, or other number across, as shown at a³, a³, a³, Figures 6 and 7,
formed on these links a¹, curved up in a pick shape at the point, and
disposed in an advancing position from the centre to the sides so as to be
able to lift a large stone when it comes in front of them.
Referring to Figure 3, the strong cast-iron side frames C carrying the
bearings and shafts of the driving barrels D, E, J, and ladder frame K
pendent from the shaft j of the latter is firmly secured on the top of a
strong iron or wood framed portable carriage O", C, with wheels C to 8
travel on the portable rails x and beams ¹ or scantling ¹, as the
excavation advances, by feeding forward the excavating machinery and
carriage. This carriage C", C², also carries the steam boiler V and
engine Y on it, convenient so that its crank shaft I would actuate
the first motion shaft H of the machine, geared by a pinion H¹ to one 3
of the wheels G, G¹, G", of the set of barrels D, E, or J, and which are
geared into. one another, so that the chains passing the latter will travel
at the same speed. In this case the upper part of the chain of buckets

page_text: is carried a considerable distance up, and laterally over supporting
rollers 9 on portable wheel frames g¹, 9", and round a reversing barrel
A, B, so as to empty the excavated material on to an angled shoot or
screen &¹ into the removing waggons M, the said barrel being carried on
a strong stayed stationary frame 2" or other equivalent, the under chain
of buckets returning in a loose bow shape at a* to the lowering internal
drum e so as to pass down the inside of the carrying ladder K round the
lower barrel o, o³, below, which is bollow without a central spindle, with
a tilting triangular weight c" within it for assisting the turning of this
lower barrel and holding the buckets 6 to their work against the face of
the "cutting" or embankment Z, Z³, being excavated, and this may be
further assisted by laying bars or blocks of iron upon the racks k,
secured to the back of the two ladder frames K below the descending
chain of buckets, the acting ascending chain of buckets a¹, b, being
stiffened and held steadily against the face of the "cutting" Z, Z³, by
rollers at their back, carried in bearings on the front side of the ladder
frames K, these side ladder frames being securely fixed together by
central transverse stays K²; and the whole ladder frame and chain of
buckets oscillate on the shaft j of the guiding barrel J within a large
slot or recess within the frame of the carriage C¹¹ from a considerable
angle to the perpendicular during its operation, or one "cutting"
without shifting the carriage supporting frames g, g³, on portable rails x
or roadway z³, on which the whole traverse.
$9
In starting to excavate with this machine the ladder K is brought up
horizontally to begin the cutting at the surface of the ground, while the
carriage O", 0³, is held or steadied by the clamps *, and the engine and
chain barrels are set to work, when the excavating will go on until the
ladder comes to the working angle to suit the particular depth of exca-
vation desired; the buckets 6 acting against the face of the "cutting
brings up the excavated material and conveys or carries it along the top
and deposits it into the waggon M at s³, all as shown in Figure 8, with
the ladder at the angle to suit this particular depth of cutting, in
which vertical position it may be maintained and carried by a hanging
chain from the carriage (as shown at M in Figure 5), and which may
then be traversed forward by its feeding gear, ³, regularly or from time
to time, and as the excavating advances. the portable rails 2, 2³, can be
removed and laid down in front and the carriage traversed on them,
having the scantling and posts 2", ³, erected below the rail roadway

page_text: .
x, x¹, when required for supporting it behind the bottom of the
ladder K.
Referring to Figure 4, the main frame C and working barrels A, B,
D, d, E, e, J, j, and ladder K and angled fixed ladder K, are all secured
and carried on one side of a strong swivelling iron or wood frame C™,
on the top of which the iron frame C, C³, is set with horizontal engine
and its cylinders Y fixed with crank shaft I just behind it, which shaft has
a pinion I¹ on one or both sides of the frame C, gearing into a large wheel
or wheels I', I", on the first motion shaft H of the driving mechanism,
so as to actuate the same by a pinion H' on it, gearing into the wheel
G¹¹ on the shaft e of the hollow barrel E, which gives motion to all tho
others by the gearing G, G², G", H", indicated by the red lines in
Figures 1 to 6, the steam boiler V, engines Y, and fuel being placed at
the other side of the swivelling frame C", to counterbalance the weight
of the new excavating machinery carried in the frame C, C', which is
carried on a strong hollow central cast iron pillar L, with broad frame
L', and steadying rollers L" beneath, swivelling on a solid central pillar
and rolling on an angled sole or a turntable I, firmly secured on a strong
iron framed traversing carriage C", C³, below, traversed on the portable
rails and roadway x, x¹, at the bottom Z', of the "cutting" Z³, being 2
made; having also rails at the side or behind the said carriage for the
waggons M, which may be temporarily attached and removed with the
carriage for the better removal of the excavated material deposited into
them over the rear barrel A, B, from an angled shoot ¹, above the
engine Y and crank shaft I, at the end of the large frame C, C. The 2
engine shaft I actuates horizontal and vertical shafts and gearing
h, i, i¹³, h², so as by a pinion i" at the bottom of the former to work in a
fixed wheel on the turntable, to swivel or fix the whole top frame
Cu by, as may be required, fitted with suitable engaging and disengaging
fixing clutches; and toothed racks may be laid on the side of the rails a
x, or on the roadway ¹; for traversing the carriage by toothed wheels
on the shaft of one pair of its traversing wheels C³, actuated also from a
transmitting shaft and gearing " from the engine, so as to feed the
carriage C", 0³, and its angled ladder frame K¹ of the buckets 6 up
against the face of the "cutting" Z, Z², to be excavated, all in this case 3
above the roadway of the apparatus, and as particularly suitable for
making railway "cuttings" and other such excavations.
It will be observed that as the whole frame and ladder of buckets are.

page_text: turned on the vertical central pillar and frame L, L³, as a horizontal
turntable in this arrangement it may be so turned and fed round by the
engine Y and gearing 3, 4, 3, as to make the rising chain of buckets
be turned and fed round radially to their excavating work across the
face of the "cutting" of earth Z, Z; being so excavated when desired as
well as traversed forward on their rails x, x³, as before described. And
in these cases also (Figures 3 and 4) the ascending and descending chain
of buckets a, a¹, b, pass round a lower barrel o carried in the bottom of
a ladder frame K³, and especially in the latter case, where that is not
oscillated, the barrel o may, when desired, be driven by a long shaft /
brought down and carried in bearings on one or both sides of the ladder
K, and geared by bevel wheels at ", ", and actuated by the former
geared to the shaft ; of the guiding barrel J at the upper part of the
ladder K. as indicated in red lines in Figure 4.
Referring to Figure 5, the main frame C, O¹, carrying the actuating
barrels A, B, D, d, E, e, and J, j, between them firmly stayed by trans-
verse stays C¹, as in the other cases, substantially as shown in the
enlarged detailed views, Figures 6 and 7, the whole being secured on the
top of a strong iron or wood carriage near the middle over a long slot or
open recess in the middle, which allows the ladder of buckets K (all
constructed and secured as described in reference to Figure 3) to be from
any angle near the surface of the ground to begin the trench down to
near the vertical direction as working positions, raised and lowered by
the chaim m and hand or motive-power windlass m³ at the rear end of
the carriage 0, 0³, and as so indicated in the red and black lines in
two of their angular working positions for outting shallow and deep
tranches according to the angle at which it is lowered and held by the
windlass m². The boiler V and engine Y are placed at the other or front
end of the carriage O¹, O³, to balance or distribute the weight more
equally on it, and a pinion I' on the crank shaft I of the engine gears
into the large wheel I on the first motion shaft H of the improved
excavating mechanism carried on the frame O, O³, which shaft by a
pinion H gears into the wheel G of the barrel d, D, in this case, instead
of that H, G³, of the barrels A, B, e, E, as shown in Figures 1, 2, and 4
respectively; but it is to be understood that the pinion H² of this first
motion shaft H of the mechanism might gear into any of the sets of
wheels Hª, G, G³, G", of the motive barrels shown in all the Figures as
geared together, and indicated in red lines in the elevations. The car-
a

page_text: riage 0, 0, is traversed (as described in reference to Figures 3 and 4)
on portable lengths of rails and scantling x¹ or other roadway, lifted
from behind and laid down in front and on each side of where the trench
is to be excavated, just as finished for the carrying and bearing and
traction wheels C³, C³, to run on, with toothed rack preferably at the
side of each rail x for toothed traction spur wheels C³ on one axle of the
carrying wheels C³ to gear into, driven by intermediate shafts and
reducing wheels, or it may be a screw and worm wheel », at a slow
speed from the engine shaft I to feed the carriage O", O³, and excavating
ladder K and chain of buckets a, a, b, forward to the cutting face Z, Z, :
of the trench Z³ being excavated. The material excavated by the rising
buckets in front of the latter at whatever angle or depth of trench it may
be cutting is brought up over the front barrels j, J, and d, D, and carried
away laterally, and delivered over the reversing and chain barrel A, B,
on to the angled shoot z¹ on to the ground or low removing waggons at 1
the side of the excavating carriage and machine or track of the trench
as it is cut. In this arrangement the wide part of the buckets & would
be made the width of the trench Z desired to be cut, or the alternate
ones might be fixed on the chain a, a, an inch or two laterally to the
opposite side, so as to make the trench a little wider than the buckets, a
and so give a little clearance for them sidewise, or for excavating broad
trenches two sets of chains and buckets, with their actuating and guiding
barrels might be mounted on the same shaft, framing, and ladders, and
have flanges on the inside resisting guide rollers k¹ for keeping the
chains steady laterally as well as in front.
Although these several modifications and applications of my improved
excavating machines C, C, Figures 1 to 5, have mainly been described
for excavating and removing the materials excavated, it will be evident
to engineers that Figures 1 and 2 and 3 and 5 are also applicable to and
for sinking and deepening or dredging deep holes, reservoirs, docks, a
harbours, estuaries, channels, trenches, or pipe tracks, or cleaning
common sewers, and for the discharging of grain and ballast from ships
or vessels and such like or analogous purposes, and of course when used
for dredging purposes the whole portable machine carried in the frame
Ơ, O', would be erected on the deck of a dredge boat, and remove or a
discharge the dredged material into hopper barges or punts at the sides
or ends of the dredger.

page_text: manner in which the same is or may be used or carried into effect,
I may observe in conclusion that I do not confine or restrict myself to
the precise details, or arrangements and adaptations which I have had
occasion to describe, delineate, or refer to, as many variations of and from
these might be made without departing from the main or essential
features of my said Invention; neither on the other hand do I claim the
forms and constructions of many of the parts of the chains and buckets,
or ladder frames or modes of attachment (which I had occasion to name
and refer to) by themselves specially, as some of these may have been
used heretofore in other excavating and dredging machines, except in so
far as these have essential reference to or form part of my said improve-
ments or Invention; but what I consider novel and original and
therefore claim as the Invention secured to me by the herein-before in
part recited Letters Patent is,-
First. The construction and arrangement of the parts of the several
modifications and adaptations of my improved excavating, dredging,
and removing machinery or mechanism, all substantially in the manner
as and for the purposes herein described and distinguished in reference to
and shown in the several Figures 1 to 5 respectively of the accom-
panying Drawings.
Second. The construction and arrangement of the parts of excavating
mechanism, carried with and upon strong substantial side frames (as
C, C',) as a portable machine, with the wheels of its chain barrels all
geared together complete, ready for either setting down on a stationary
sole as in Figures 1 and 2, or a portable traversing carriage as. in
Figures 3 to 5, and actuated by any local portable engine or any other
motive-power shaft, all substantially in the new of improved manner,
and for the purposes herein described and shown in the accompanying
Drawings.
Third. The carrying of the upper part or loop of the traversing chain
of buckets which descends and ascends for excavating purposes away
some distance laterally over a delivery end barrel, cither upon the
portable frame C, C, or other frames at a distance, and bring the inverted
return chain of buckets over a hollow lowering barrel so as to descend
vertically or at an angle nearly parallel to the acting or ascending line
of buckets, all substantially in the new or improved manner herein
described and shown in the accompanying Drawings.

page_text: Fourth. The construction and use of a hollow drum to receive the
return line or chain of buckets of excavating machinery to enable these
chains to be led to and from it at different angles, and nearly parallel to
the acting or ascending line or set of chain buckets, substantially as
herein described and shown in the accompanying Drawings.
In witness whereof, I, the said Simon Robertson, have hereunto set
my hand and seal, this Eleventh day of February, in the year
of our Lord One thousand eight hundred and seventy-four.
Witness,
JOHN THOMSON,
Patent Agent,
62, Buchanan Street,
Glasgow.
SIM. ROBERTSON. (L.S.)