IMPROVEMENTS IN GROUND OR EARTH SCREWS
Year: 1861

page_text: LETTERS PATENT to Frederick Johnson, of 12, North Street, in the City
of Westminster, Civil Engineer, for the Invention of "IMPROVEMENTS
IN GROUND OR EARTH SCREWS."
Sealed the 22nd April 1862, and dated the 20th November 1861.
PROVISIONAL SPECIFICATION left by the said Frederick Johnson at
the Office of the Commissioners of Patents, with his Petition, on the
20th November 1861.
I, FREDERICK JOHNSON, of 12, North Street, in the City of Westminster;
Civil Engineer, do hereby declare the nature of the said Invention for "IM-
PROVEMENTS IN GROUND OR EARTH SCREWS," to be as follows, and consist in
making the periphery of the flange of the screw with a number of teeth similar
to a circular saw, and arranged so as to assist the pitch of the screw, thereby.
enabling it to cut its way into the ground with greater facility than those at
present used with a plain.and unbroken flange, or the screws may be made by
having only a portion of its periphery with teeth, and in this case a projection
would be made at its cutting edge, so that the remainder of the screw which is
of a lesser diameter, would follow in the opening made by the said projection.

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, FREDERICK
JOHNSON, of 12, North Street, in the City of Westminster, Civil Engineer,
send greeting.
WHEREAS Her most Excellent Majesty. Queen. Victoria, by Her Letters
Patent, bearing date the Twentieth day of November, in-the-year of our Lord
One thousand eight hundred and sixty-one, in the twenty-fifth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said Frederick Johnson, Her special licence that I, the said
Frederick Johnson, my executors, administrators and assigns, or such
others as I, the said Frederick Johnson, my executors, administrators, and
assigns, should at any time agree-with, and no others, from time to time and
at all times thercafter during the term therein expressed, should and law-
fully 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 GROUND OR EARTH SCREWS," upon the condition (amongst
others). that I, the said Frederick Johnson, 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 Frederick Johnson, 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:-
This Invention consists in making the periphery of the flange of the screw
with a number of teeth similar to a circular saw, and arranged so as to assist
the pitch of the screw, thereby enabling it to cut its way into the ground with
greater facility than those at present used with a plain unbroken flange; or the
screws may be made by having, only a portion of its periphery with teeth, and
in this case a projection would be made at its cutting edge, so that the remain-
der of the screw which is of a lesser diameter, would follow in the opening made
by the said projection.".
"
The accompanying Drawing fully illustrates my Invention, shewing several
of the arrangements of the teeth on the edge of the periphery of screw. Fig. 1,

page_text: is an elevation of a wrought-iron pile and cast-iron screw; Fig. 2 is an eleva-
vation of a hollow cast-iron-pile with teeth or a serrated-edge at-the-bottom-of-
the pile; Fig. 3 is a plan of a screw with teeth around its entire periphery;
Fig. 4 is a plan of a screw shewing an arrangement of teeth, commencing at
the cutting edge and at four other points; Fig. 5 is a plan of a screw similar
to Fig. 3, but having no teeth on its cutting edge, the first tooth commencing at
the junction of periphery of screw with the cutting edge; Fig. 6 is a plan of
a screw similar to Fig. 4, the first tooth being arranged similar to that on
Fig. 5; Fig. 7 is a plan of a screw having teeth at its cutting edge only; and
Fig. 8 is a plan of a screw the same as Fig. 7, with the exception that the
last tooth is made to project beyond the periphery.
Having thus fully described the particulars and nature of my Invention, it
must be understood that I do not confine myself to any particular form of screw
arrangement of teeth, neither to the description of tooth or depth of same,
but what I claim is making the periphery or flange of the screw with a num-
ber of teeth arranged so as to assist the pitch of the screw, thereby enabling it
to cut its way into the ground with greater facility as herein fully described,
also the application of the saw or serrated edge at the bottom of the cast-iron
screw pile, shewn in Fig. 2, in conjunction with the teeth on the periphery of
the same.
In witness whereof, I, the said Frederick Johnson, have hereunto set my
hand and seal, this Twentieth day of May, in the year of Our Lord
One thousand eight hundred and sixty-two.
FREDERICK JOHNSON.
(L.S.)