ImprovEMENTS IN ANCHORS
Year: 1863

page_text: LETTERS PATENT to William Rodger, of No. 9, Shawfield Street, Kings
Road, Chelsea, in the County of Middlesex, Captain in the Royal Navy,
for the Invention of "ImprovEMENTS IN ANCHORS."
Scaled the 28th July 1868, and dated the 29th April 1863.
PROVISIONAL SPECIFICATION left by the said William Rodger at the
Office of the Commissioners of Patents, with his Petition, on the
29th April 1868.
I, WILLIAM RODGER, of No. 9, Shawfield Street, Kings Road, Chelsea, in
the County of Middlesex, Captain in the Royal Navy, do hereby declare the
nature of the Invention for "IMPROVEMENTS IN ANCHORS," to be as follows:--
My said Invention of "Improvements in Anchors" relates to those parts
which are usually termed the "crown," the "arms," and the "palms," and the
object I have in view is to obtain a greater amount of strength and holding
power with a given weight of iron. The additional strength is obtained partly
by making the "armis" shorter than is usual in proportion to the length of
the "shank," and partly by their sectional form. The sectional form of the
"shank "is rectangular at its junction with the arms, and square at the

page_text: "small" close to the collar for the stock. But the sectional form of the
"arms" is widely different from that of any other anchor now in use, being of
a wedge-form, varying in sharpness from the throat to the head of the palms.
The back part of the "arms" is made parallel from palm to palm, and much
thicker than their front part, which is tapered in the direction of the point.
In an anchor of 64 cwt., for instance, the back part of the arm at the head of
the palm is 8 inches thick, whilst the front part is only 1 inches thick, and
its breadth in a line parallel to tho shank is about 17 inches. By this it will
be seen that the transverse section at this part forms a truncated wedge about
17 inches in length, 8 inches thick at its baso, and 1 inches thick at its point,
and the effective length of the wedge increases throughout the whole length of
the "arm "as the shank sinks below the horizontal line. The additional
holding power is obtained partly by the peculiar form of the arm above
described, which when the anchor is dragged forces the ground out laterally
without disturbing it in front in the slightest degree, and consequently anchors
of this description are not liable to become "shed" and rise out of the ground.
And further, it is partly obtained by the peculiar form of the palm, which has
its face or front part double concave, somewhat similar to that of a former
anchor of my Invention, for which Letters Patent were granted to me on the
10th November 1853 (No. 2603), but with the addition of a border for the
purpose of confining a portion of the soil through which it is dragged, and also
a large countersunk hole on the back of it for the same purpose, as well as for
the purpose of saving a considerable weight of iron where it would be com-
paratively of no use. By this contrivance the soil thus confined on both sides
of the "palm," when the arm has penetrated to a certain depth, unites with
the surrounding ground, and by their cohesive attraction render it much more
difficult to start the anchor, especially if the ground be of a very adhesive
quality, which is frequently found to be the case. The same principle obtains
in regard to the crown, which is made much longer than usual with a large
countersunk hole in its centre, whereby a very considerable weight of iron is
saved, and its place being filled with the soil in which the anchor is placed it
adheres to the ground on both sides, and thereby greatly augments the holding
power of the anchor. I may also state that the "point of the palm," which is
about one-fifth part of the length of the arm forms an angle of about 60° with
the shank, whilst the edge of the palin makes an angle of only about 20°. By
this arrangement the penetrating tendency is increased as well as the lateral
resistance, and to such an extent that the anchor completely buries itself. Its
form allows the arm to penetrate until the shank forms an angle of about 20°

page_text: with the ground, in which position the extremity of the upper arm would be
beneath the surface, and consequently not liable to be fouled.
It is only necessary now to add that I purpose making the stream and kedge
anchors on precisely the same principle as the bower anchor above described,
but as they do not require so much strength I intend to make them con-
siderably longer in order to obtain a greater amount of holding power with the
same weight. And for the convenience of carrying them out in a boat I
intend making them without "palms," and therefore by way of distinction they
may be designated "pickaxe anchors."
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said William Rodger in the Great Seal Patent Office on the
27th October 1863.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
RODGER, of No. 9, Shawfield Street, Kings Road, Chelsea, in the County of
Middlesex, Captain in the Royal Navy, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Twenty-ninth day of April, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-sixth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said William Rodger, Her special licence that I, the said William Rodger, my
executors, administrators, and assigns, or such others as I, the said William
Rodger, 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 ANCHORS,"
upon the condition (amongst others) that I, the said William Rodger,
my executors or administrators, by an instrument in writing under my, or
their, or one of their bands and seals, should particularly describe and ascer-
tain the nature of tho 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 William Rodger, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed,

page_text: to be particularly described and ascertained in and by the following statement
thereof, that is to say :-
My said Invention of "Improvements in Anchors" relates to those parts
which are usually termed the "crown," the "arms," and the "palms," and
the object I have in view is to obtain a greater amount of strength
and holding power with a given weight of iron. The additional strength is
obtained partly by making the "arms" shorter than usual in proportion to
the length of the shank (that is to say, about one-fourth part instead of about
one-third), and partly by their sectional form. The sectional form of the
"sbank" is rectangular at its junction with the arms, and square at the shank
close to the collar for the stock. But tho sectional form of the "arms" is
widely different from that of any other anchor now in use, being of a wedge
form varying in sharpness from the throat to the head of the palms. The
back part of the "arms" is made parallel from palm to palm, and is much
thicker than their front part, which is tapered in the direction of the point, as
will be seen by the annexed Drawing. And the "arms" from the crown
to the head of the palms being much broader in the direction of the strain
than is usual gives them a great increase of strength. The additional holding
power is obtained partly by the pecular form of the "arms" above described,
which when the anchor is dragged forces the ground out laterally without dis-
turbing it in front, and, consequently anchors of this description are not liable
to become "shod" and riso out of the ground as frequently happens with
anchors of the ordinary construction with large palms. And, further, the
additional power of holding is partly obtained by the peculiar form of the
"palms," which have their front parts double-concave somewhat similar to
those of a former anchor of my Invention, for which Letters Patent were
granted to me on the 10th November 1853 (No. 2608), but with the addi-
tion of a border for the purpose of confining a portion of the soil through
which the anchor is dragged, and also a large conical hold or recess in their
back part for the same purpose as well as for the purpose of saving iron where
it would be of no use. By this construction the soil thus confined on both
sides of the "palm" when the arm has penetrated to a certain depth, unites
with the surrounding ground, and by their cohesive attraction render it much
more difficult to start the anchor, especially if the ground be of a very adhe-
sive quality, which is frequently found to be the case. And in all kinds of
ground this construction augments the holding power of the anchor, for should
it start, which may happen by riding, with too short a scope of cable, the addi-
tional friction thereby produced will greatly assist in causing it again to bite.

page_text: The same principle obtains in regards to the "crown," which is made much
longer than usual, which admits of a larger and countersunk hole being made
in its centre, whereby a very considerable weight of iron is saved, and its
place being filled with the soil in which the anchor is buried, it adheres to the
ground on both sides of it, and considerably augments the holding power of
the anchor. I may also state that the point of the "palm "which is about one-
fifth part of the length of the "arm" forms an angle of about 60° with the
shank, whilst the edge of the "palın" makes an angle of only about 20° with
it. By this arrangement or construction the penetrating tendency is increased
as well as the lateral resistance, and to such an extent that the anchor com-
pletely buries itself. The shape of the "palm" in fact allows the arm to
penetrate until the shank forms an angle of about 20° with the ground, in
which position the extremity of the upper arm would be beneath the surface,
and consequently not liable to be fouled.
Instead of drawing down or reducing the thick end of the shank into the
form of a thin tenon (as is usual), for the purpose of receiving the tenon of one
of the "arms" on each side of it (which combination jointly forms the "crown,")
and when "shut" filling the vacant spaces between the thick parts of the arms
and the tenon of the shank with loose iron (usually called filling the holes)
I make the thick end of the shank in the shape of a cross, which is formed
out of the solid iron under the forge hammer, and by this means solid throats
are obtained as will be seen by the Drawing, and the necessity of using filling
iron is removed, the "arms" being connected with the shank by means of plain
scarphs, the points of which may be made to overlap the solid parts of both
in the same manner as in welding the links of a chain, or any other pieces of
iron. The "palms" and a considerable part of the "arms," and likewise the
middle of the stock are formed in cast-iron dies or moulds, into which they
are driven by means of the forge hammer. The hole in the "crown" is
drilled, and the holes in the middle and ends of the "stock" as well as the
holes for the shackle bolt and stock key are drilled and slotted, but tho
conical hole in the back of the "palms" is punched whilst the palm is in
the die.
The stream and kedge anchors are made on precisely the same principle as
the bower anchor above described, but as they do not require so much strength,
I intend to make them considerably longer in order to obtain a greater amount
of holding power with the same weight, and for the convenience of carrying
them out in a boat I prefer making them without "palms" as will be seen
by tho Drawing, and therefore by way of distinction they may be designated
'pick-axe anchors."
66

page_text: "
Sheet 1, Figure 1, is an elevation or side view of an anchor made according
to my present improvements exhibiting a section of the middle of the stock
and an edge view of the shackle. Figure 2 is a plan of the same anchor
together with the stock, stock key, and key guide, and also of the shackle.
Figure 3 is a front view of the stock (detached from the anchor) with the
key guide laid across the hole to show that it keeps the key entirely clear of
the stock. Figure 4 is a back view of the stock by which it will be scen
that in the middle (through which the shank of the anchor passes) the front
is made wider than the back part both vertically and laterally. Figure 5 is
a section of the middle part of the stock, by which it will be seen that the
projection on either side of the hole is equal to the size of the shank at the
"small" and this projection (if the anchor be dragged) makes a rut for the
sbank of the anchor to fall into, which in effect is tantamount to lengthening
the "arm," and moreover this enlargement in the middle of the stock adds
materially to the holding power of the anchor, as was the case with the "stock"
of my former anchor, but not to the same extent. Figures 6, 7, and 8, are
sections of the "stock" taken at the parts indicated by the dotted lines.
Figure 9 is a side view of the "square" of the anchor shewing the holes for the
shackle bolt, stock, key, and key guide, but without the stock, I may here
remark that in order to prevent the key guide from bending in driving in the
key, I insert a piece of teak or any other suitable wood into the key hole
at a, a, and very nearly flush with the front part of the "stock," and this piece
of wood is kept in its place by means of a small iron bolt or pin having a
countersunk head at one end and rivetted at the other as shown in this Figure
and also in Figure 1. Figure 10 is a plan of the same showing also the stock
key, and key guide by means of which the "stock" is secured in its proper place;
and I may remark that the key and key guide are slightly tapered in opposite
directions so as to bind the stock firmly against the collar on the shank of the
anchor. Figure 11 is an edge view of the stock key resting upon the key
guide. Figures 12 and 13 are sections of the "shank" taken at the dotted lines;
Figures 14, 15, 16, and 17 are sections of the "arms" taken at the dotted
lines which are the shortest distances across at those parts. Figure 18 is a
section of the "arm" on a line parallel to the "shank" exhibiting in the
clearest manner the extension of its wedge form when the anchor is buried up
to the shank, and presenting a large surface to the lateral resistance of the
ground through which it is dragged, but owing to its sharpness it does not

page_text: "
materially disturb it in front, and consequently anchors made according to this
plan cannot possibly become "shod." Figures 19, 20, and 21 are sections of
the "
arm at the parts indicated by the dotted lines which form angles of
about 18 with the "shank," and which angles would represent the relative
position of the surface of the ground in regard to the "shank" when the
anchor is buried up to the extremity of the upper arm, thus showing the still
further extension of the wedge form of the "arm" when it has penetrated to
its maximum depth, that is to say, when the anchor is completely buried, which
is known to be the case when the ground is even moderately soft. Figure 22
is a front view of the "arm" and "palm," showing the border on the latter and
herein-before mentioned. Figure 23 is a section of the "palm" taken at the
dotted line a, a, in Figure 22, and exhibiting the cavities or indentations on
its face or front part for the purpose of confining a portion of the soil as
berein-before described, and likewise for the purpose of saving iron where it
would be rather detrimental than otherwise, inasmuch as weight at the
extremity of the "arms" renders it more difficult to "cant" the anchor.
Figure 24 is a back view of the "arm” and “palm," exhibiting the form and
size of the conical hole in the back of the latter, and already mentioned, the
depth of which is equal to one-third part of its diameter and is shown by
dotted lines in Figure 1. The form of the countersunk hole in the crown is
shown by dotted lines at a, in this Figure, and also by dotted lines at a in
Figure 2. Figuro 25 is a side view of the " crown" or cross in the rough
ready to receive the arms. Figuro 26 is a back view of the "crown" and
parts of the arms in the rough ready for "shutting," proper allowance being
mado for heating and working down to the required dimensions. The dotted
circle at the "crown," is simply to shew that the length of the "crown" in
all sizes determines the position of those parts of the "shank" and arms
usually termed (by anchor smiths) the "butt ends."
Sheet 2, Figure 1, is an elevation or side view of a stream anchor or kedge
made according to my present improvements, exhibiting an edge view of the
"shackle" but without the stock; Figure 2 is a plan of the same stream or
kedge anchor, together with the stock and shackle; Figures 3 and 4 are
sections of the stock taken at the parts indicated by the dotted lines;
Figures 5 and 6 are sections of the shank taken at the dotted lines; Figures
7, 8, 9, and 10 are sections of the "arms," taken at the dotted lines, which
are the shortest distances across at those parts; Figure 11 is a section of the
arm in a line parallel to the shank; Figures 12, 13, and 14 are sections of
the "arm" at the parts indicated by the dotted lines, which form angles of

page_text: about 17 with the "shank," and to which the same remarks apply as in the
case of the "bower anchor," already described; Figure 15 is a front view of
the arm; Figure 16 is a section of the "arm" taken at the dotted line a, a,
by which, as well as by Figure 15, it will be seen that the stream and kedge
anchors have literally no palms, and therefore may properly be called the
'pickaxe anchors." Figure 17 is a back view of the "arm," exhibiting the
form and size of the oblong hole or recess close to the point, the depth of
which is equal to half its breadth, and is shown by dotted lines in Figure 1.
The properties of this hole, as well as those of the countersunk hole in the
crown, are the same as those in the "bower anchor," already described.
The mode of shutting is also precisely the same, and therefore need not be
repeated.
arms,"
Having thus described the nature of my Invention of "improvements
in Anchors," and the manner in which the saine is to be carried into effect,
it will be understood in regard to the "bower anchor "(Sheet 1) also the
stream and kedge anchor (Sheet 2) that it is peculiarly constructed in
respect to the form of the "crown," which is made much longer than usual,
with a large countersunk hole in its centre for the purposes herein specified,
and in the shape of a cross, in order to obtain solid throats, as well as a more
efficient mode of "shutting." Also in respect to the form of the "
which are made parallel on the outside or back part, and by shortening the
radius of the front part, and making the "arm" from the "crown" to the head
of the "palms" much broader in the direction of the strain than is usual
(but in keeping with the additional length of "crown") I obtain a more
extended wedge-form and corresponding lateral resistance, as is clearly
exhibited by the various transverse sections shown in the annexed Drawing.
Also in respect to the peculiar form of the "palms," having points much
longer than usual, and converging to the throat at an angle of about 60° with
the "shank," whilst the edge of the "palm" makes an angle of only about
20° with it, as shewn by the Drawing, and having also a border on their face
or front part, with a large conical hole in their back part for the purposes
herein specified. And also in making the "arms" shorter than usual in pro-
portion to the length of the "shank," whereby greater strength is obtained,
and also a greater penetrating tendency, causing the anchor completely to bury
itself, and moreover, admitting of a shorter "stock" than would be necessary
with "arms" of the usual length; admitting, also, of shorter "cat beads,"
and causing less projection from the ships bow when stowed, consequently
less liable to hook other ships in crowded anchorages.

page_text: I would remark in respect to the construction of the "stream and kedge
anchors," (Sheet 2,) which are literally "pick-axes," that they are much more
convenient for carrying out in a boat, and also for stowing, either in the
chains or on the ship's deck.
In witness whereof I, the said William Rodger, have hereunto set my
hand and seal, this Twenty-fourth day of October, in the year of our
Lord One thousand eight hundred and sixty-three.
W. RODGER. (L.S.)