IMPROVE- MENTS IN STEAMERS FOR TOWING PURPOSES
Year: 1873

page_text: LETTERS PATENT to James Howden, of Glasgow, in the County of
Lanark, North Britain, Engineer, for the Invention of "IMPROVE-
MENTS IN STEAMERS FOR TOWING PURPOSES."
Sealed the 2nd April 1874, and dated the 9th October 1873.
PROVISIONAL SPECIFICATION left by the said James Howden at the
Office of the Commissioners of Patents, with his Petition, on the
9th October 1873.
I, JAMES HOWDEN, of Glasgow, in the County of Lanark, North
Britain, Engineer, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN STEAMERS FOR TOWING PURPOSES," to be as follows,
that is to say :-
-
This Invention has for its object to obtain a superior and more
efficient steamer for towing or hauling other vessels, by arranging and
constructing its machinery or propelling apparatus in such relation to its
displacement or size as that the greatest possible proportion of its pro-
pelling power may be utilised in towing, and the least be required for
propelling itself through the water. To this end the size and displacement
of the improved towing steamer is made not more than sufficient for safety
and for conveniently carrying the machinery, and to admit of the increased

page_text: power relatively to the size being properly and satisfactorily developed
and utilised the vessel is fitted with two screw propellers of com-
paratively large diameter, such propellers being one at each end on the
same shaft or line of shafting or on separate shafts in the same line and
connected by gearing to revolve simultaneously. The propellers are of
a size to project considerably below the body of the vessel and even
below what would be an ordinary keel, and in one modification they are
arranged to work in openings in propeller frames (corresponding to the
stern frames of ordinary screw steamers) the keel if of the ordinary
depth amidships, being curved down on approaching the propeller
frames to avoid abrupt projections which would be liable to catch on
ropes or other objects. If preferred however the keel may be made
throughout of sufficiently increased depth to reach the bottom of the
propeller frames, or the middle of the vessel's bottom may be extended
downwards in a curved projecting form to an ordinary keel placed
sufficiently low.
The vessel is shaped with similar and sufficiently fine lines at both
ends, and the propellers are by preference two bladed, the blades of one
being at right angles to those of the other. Three bladed or other
propellers may however be used in some cases.
The vessel may be fitted with rudders at each end and can be
propelled in either direction, the rudder that happens to be forward
being locked to act as a stem.
The vessel may be fitted at both ends for the attachment of the towing
ropes or hawsers, but it will generally be sufficient to be so fitted at one
end only.
In another modification each screw propeller is overhung beyond an
outer post, the rudder being fitted in openings within such post above
and below the shaft or in a single opening above the shaft. The post is
extended down as low as the bottom of the circle swept through by the
propeller the keel being curved down to it or being of an increased
depth to be level with it.
In some cases a single propeller at the stern may be adopted, the

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Howden in the Great Seal Patent Office
on the 8th April 1874.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
HOWDEN, of Glasgow, in the County of Lanark, North Britain,
Engineer, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Ninth day of October, 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 James Howden, Her special licence
that I, the said James Howden, my executors, administrators, and
assigns, or such others as I, the said James Howden, 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
STEAMERS FOR TOWING PURPOSES," upon the condition (amongst others) that
I, the said James Howden, my executors or 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 James Howden, 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
Drawings, that is to say :—
My said Invention has for its object to obtain a superior and more
efficient steamer for towing or hauling other vessels by arranging and
constructing its machinery or propelling apparatus in such relation to

page_text: propelling power may be utilised in towing and the least be required for
propelling itself through the water.
And in order that my said Invention and the manner of performing
the same may be properly understood, I hereunto append a Sheet of
explanatory Drawings to be herein-after referred to, and representing
two steamers for towing purposes as constructed with my improvements.
In these Drawings the same reference numerals are used to mark the
same or like parts wherever they are repeated.
Figures 1 and 2 are vertical longitudinal sections, and Figures 3 and 4
are transverse vertical or midship sections.
For the purposes of my Invention the size or displacement of the
towing steamer is made not more than sufficient for safety and for
conveniently carrying the machinery, and to admit of the increased
power relatively to the size being properly and satisfactorily developed
and utilised, the vessel is fitted with two screw propellers 1, 2, of com-
paratively large diameter, such propellers being one at each end on the
same shaft 3 or line of shafting.
In the midship sections, Figures 3 and 4, the boilers 4 are indicated
as being arranged so that the propeller shaft 3 may pass between them,
but if it is considered more convenient to have a large or other boiler
in the centre, such boiler may be constructed with a large tube for
the propeller shaft 3 to pass through, or the propellers may be on
separate shafts in the same line and connected by gearing to revolve
simultaneously. The propellers 1, 2, are of a size to project considerably
below the body of the vessel and even below what would be the ordinary
keel, as at 5, of a commercial steamer as defined by Lloyd's rules, and
in one modification, shown in Figure 1, they are arranged to work in
openings in propeller frames 6, 7, (corresponding to the stern frames of
ordinary screw steamers), the keel if of the ordinary depth amidships,
as at 5, being curved down as at 8, 9, on approaching the propeller
frames 6, 7, to avoid abrupt projections which would be liable to catch
on ropes or other objects. If preferred however the keel may be made
throughout of sufficiently increased depth to reach the bottom of the
propeller frames 6, 7, as shown in Figures 2 and 3, or the middle of the
vessel's bottom may be extended downwards in a curved projecting form
as shown at 9, in Figure 4, to an ordinary keel 10 placed sufficiently
low. The space between the curved plates 9 is by preference filled with

page_text: cement in which a passage is formed for draining bilge water and
leading it to the pumps.
The vessel is shaped with sufficiently fine lines at both ends, but
preferably with the end which will be more frequently in advance,
shaped with bow lines merely modified to suit the introduction of the
forward propeller frame 6. The propellers 1, 2, are by preference two-
bladed, the blades of one being at right angles to those of the other, and
they are both by preference set with their propelling surfaces facing in
the same direction. Three-bladed or other propellers may however be
used in some cases.
The vessel may be fitted with rudders 11, 12, at each end and can be
propelled in either direction, the rudder that happens to be forward
being locked to act as a stem.
The vessel may be fitted at both ends for the attachment of the towing
ropes or hawsers, but it will generally be sufficient if one end only is so
fitted.
In the modification of my improved towing steamer, shown in
Figure 2, each screw propeller 1, 2, is overhung beyond an outer
post 13, 14, the rudder 15 being fitted in openings within such post 13,
partly above and partly below the propeller shaft 3, as shown at the
right hand end of the Figure, or entirely in a single opening above the
shaft 3, as shown at the other end. The post 13, 14, is in each case
extended down as low as the bottom of the circle swept through by the
propeller 1, 2, the keel being of an increased depth to be level with it, as
shown in Figure 2, or being curved down to it in a manner similar to
what is shown in Figure 1.
In some cases a single propeller at the stern may be adopted, the other
features of my improved construction being however retained so far as
regards the after part of the vessel, and when a single propeller is thus
used it may be made of still larger diameter proportionally and so as to
reach further below the main body of the vessel.
Having thus particularly described my said Invention, and the manner
of performing the same, I have to state that I do not restrict myself to
the preciso details herein described or delineated, but that what I
believe to be novel and original and claim as the Invention secured to
me by the herein-before in part recited Letters Patent is,—

page_text: 1. The constructing and proportioning of steamers and the combining
of their parts, substantially in the improved modes and for the purposes
herein-before described.
2. The fitting of a steamer for towing purposes with two screw
propellers, one at each end and on the same line of shafting and reaching &
below the main body of the vessel, as herein-before described.
3. The constructing of a steamer for towing purposes with one screw
propeller of large diameter and extending below the level of an ordinary
keel, as herein-before described.
In witness whereof, I, the said James Howden, have hereunto 1
set my hand and seal, this Seventh day of April, in the year of
our Lord One thousand eight hundred and seventy-four.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
JAMES HOWDEN. (L.S.)