Improvements in Portable Blackboards.
Year: 1896

page_text: Date of Application, 11th July, 1896
Complete Specification Left, 20th Feb., 1897-Accepted, 1st May, 1897
IONAL ST ECIFICATION.
Improvements in Portable Blackboards.
We, THE COMPARATIVE SYNOPTICAL CHART COMPANY LIMITED, and
WALTER LYON SINTON, Gentleman, all of 77 Victoria Street, in the City of
Toronto, in the County of York, and Province of Ontario, Canada, do hereby
declare the nature of this invention to be as follows:-
The object of this invention is to devise a simple and convenient portable black-
board especially adapted for teaching history according to Scaife's Comparative
and Synoptical System and it consists essentially of a blackboard detachably
connected to a knock-down frame or easel and provided with a vertical sliding
straight-edge having a changeable scale connected thereto substantially as
hereinafter more particularly described.
Fig. 1 is a perspective view of a blackboard constructed in accordance with this
invention.
Fig. 2 is a side elevation of the same.
Fig. 3 is an enlarged sectional view of the blackboard proper.
Fig. 4 is a plan view of the top of the blackboard.
Fig. 5 is a detail showing the cross bar of the frame and its mode of connection
to the standards.
In the drawings like letters, of reference indicate corresponding parts in the
different figures.
A are feet suitably shaped to rest on the floor and which may also if desired be
provided with castors.
Bare two standards having jaws a formed at their lower ends which jaws
embrace the feet A and are connected thereto by screws or pins as shown.
S are supports formed on the standards to receive the lower edge of the black-
board D. These supports may be either formed by the projecting part of the
standard as shown or by a pin or other device connected thereto.
C is a cross bar having hooked metal lugs b connected to its ends.
I are plates slotted at d and connected to the sides of the standards B overlying
recesses formed therein. The slots d are of sufficient size to receive the hooked
meta! lugs b which when inserted are dropped to engage with the lower edges of the
slots so that the standards are rigidly secuted together by the cross-bar. The
upper portions of the standards above the supports S are preferably though not
necessarily tapered..
E are loops secured to the upper edge of the black board and adapted to embrace
he upper ends of the standards B as shown when the blackboard is resting on the
upports S.
A small retaining piece e is advantageously connected to the front of each
upport S to prevent the lower edge of the blackboard being accidentally drawn off
he support though the same effect would be obtained by grooving the upper edge
f the support.
H are guide-ways advantageously shaped as shown in cross-section to reduce the
rictional surfaces and connected respectively to the top and bottom of the face of.
he blackboard. In these guide-ways two heads J are adapted to slide. These
eads are connected by a vertical straight edge G.
fare slight recesses formed in the heads J so that the ends of the scale K may
e sprung therein. The centre of the scale may be secured to the vertical straight

page_text: edge by means of a hand-screw L which also serves as a handle to move the
vertical straight edge with its connected scale.
When it is desired to knock down the blackboard for transportation the black-
board proper is lifted from the support S and the loops E disengaged from the
upper ends of the standards. The cross-bar C is then removed by disengaging its
hooked lugs from the plates I. Then the standards may be disengaged from the
feet A by removing the connecting pius or screws and the blackboard may then be
packed together ready for shipment or removal to a new situation.
By reversing the process the blackboard may be again put into condition
for use.
As the blackboard is intended largely for use with Scaife's Comparative and
Synoptical Historical Charts the scale shown in the drawing is one of years each
division of the scale representing a period of five years.
By placing a crayon against a division on the scale representing any particular
year and holding the chalk firmly against the straight edge while the latter is
moved in a horizontal direction a line may be drawn across the board indicating
any particular year. Vertical lines may be drawn by drawing the chalk
longitudinally along the straight edge. By these two actions parallelograms
such as shown on the board may be constructed and filled in with the names of
personages wars or various historical periods.
The value of the blackboard and scale in constructing diagrams showing
contemporaneous events in the history of different countries is well illustrated
by the examples shown where various facts and events in Canadian and English
history are shown side by side. The unit of the scale L of years may be made by 1,
5, 10, or any desired number of years so that contemporaneous events may be
presented on varying scales as may be deemed advisable. As the scales are
removable the year scale may be detached and an ordinary scale of feet and inches
substituted for making rough plaus to scale or scales indicating varying number of
feet to the inch may be placed on the straight edge for making drawings to any
desired scale; thus the black board may be made of use to architects for designing
purposes or for various other forms of geometrical or mechanical drawing.
It is well known that blackboards bave been made with vertically sliding straight
edges but in such there is friction at either side and they are therefore liable to
jam or wabble but with my horizontally sliding straight edge the friction is
almost entirely on the lower guide and that as previously described has its lower
frictional surface largely reduced in area so that a slight touch or push will send
the vertical straight edge from one end of the board to the other thus overcoming
the above difficulty without the use of roller or ball bearings.
From the above description it will be seen that a very simple and convenient
portable blackboard has been devised well adapted for the use of teachers architects
and draftsmen of all kinds.
We, THE COMPARATIVE SYNOPTICAL CHART COMPANY, LIMITED, and
WALTER LYON SINTON, Gentleman, all of Number 77 Victoria Street, in the
City of Toronto, in the County of York, and Province of Ontario, Canada, do
hereby declare the nature of this invention and in what manner the same is to

page_text: statement:―
The object of this invention is to devise a simple and convenient portable black-
board especially adapted for teaching history according to Scaife's Comparative
and Synoptical System, and it consists, essentially, of a blackboard detachably
connected to a knock-dowa frame or easel and provided with a vertical sliding
straight-edge having a changeable scale connected thereto, substantially as
hereinafter more particularly described.
Referring to the drawings left with the Provisional Specification-
Figure 1, is a perspective view of a blackboard constructed in accordance with
this invention.
Figure 2, is a side elevation of the same.
Figure 3, is an enlarged sectional view of the blackboard proper.
Figure 4, is a plan view of the top of the blackboard.
Figure 5, is a detail showing the cross bar of the frame and its mode of
connection to the standards.
In the drawings, like letters of reference indicate corresponding parts in the
different figures.
A, are feet suitably shaped to rest on the floor and which may also, if desired,
be provided with castors.
B, are two standards having jaws a formed at their lower ends, which jaws
embrace the feet A, and are connected thereto by screws or pins, as shown.
S. are supports formed on the standards to receive the lower edge of the
blackboard D. These supports may be either formed by the projecting part of
the standard, as shown, or by a pin or other device connected thereto.
C, is a cross-bar having hooked metal lugs b connected to its ends.
1, are plates slotted at d, and connected to the sides of the standards B,
overlying recesses formed therein. The slots d are of sufficient size to receive
the hooked metal lugs b, which, when inserted, are dropped to engage with the
lower edges of the slots so that the standards are rigidly secured together by the
cross bar. The upper portions of the standards above the supports S, are
preferably, though not necessarily, tapered.
E, are loops secured to the upper edge of the blackboard and adapted to
embrace the upper ends of the standards B, as shown, when the blackboard is
resting on the supports S.
A small retaining piece e is advantageously connected to the front of each
support S, to prevent the lower edge of the blackboard being accidentally drawn
off the support, though the same effect would be obtained by grooving the upper
edge of the support.
H, are guide ways advantageously shaped as shown in cross-section to reduce
the frictional surfaces, and connected respectively to the top and bottom of the
face of the blackboard. In these guide ways two heads J, are adapted to slide.
These heads are connected by a vertical straight edge G. fare slight recesses
formed in the heads J, so that the ends of the scale K, may be sprung therein.
The centre of the scale may be secured to the vertical straight edge by means
of a hand-screw L, which also serves as a handle to move the vertical straight
edge with its connected scale.
When it is desired to knock down the blackboard for transportation, the
blackboard proper is lifted from the support S, and the loops E, disengaged from
the upper ends of the standards. The cross-bar C, is then removed by
disengaging its hooked lugs from the plates I. Then the standards may be
disengaged from the feet Ä, by removing the connecting pins or screws, and the
blackboard may then be packed together ready for shipment or removal to a new
situation. By reversing the process, the blackboard may be again put into
condition for use.
As the blackboard is intended largely for use with Scaife's Comparative and

page_text: Synoptical Historical Charts, the scale shown in the drawing is one of years, each
division of the scale representing a period of five years.
By placing a crayon against a division on the scale representing any particular
year and holding the chalk firmly against the straight edge while the latter is
oved in a horizontal direction, a line may be drawn across the board indicating
any particular year. Vertical lines may be drawn by drawing the chalk
longitudinally along the straight edge. By these two actions, parallelograms,
such as shown on the board, may be constructed and filled in with the names of
personages, wars or various historical periods.
The value of the blackboard and scale in constructing diagrams showing
contemporaneous events in the history of different countries is well illustrated by
the examples shown, where various facts and events in Canadian and English
history are shown side by side. The unit of the scale L, of years, may be made
by 1, 5, 10, or any desired number of years, so that contemporaneous events may
be presented on varying scales as may be deemed advisable. As the scales are
removable, the year scale may be detached and an ordinary scale of feet and inches
substituted for making rough plans to scale, or scales indicating varying number
of feet to the inch, may be placed on the straight edge for making drawings to
any desired scale; thus the blackboard may be made of use to architects for
designing purposes or for various other forms of geometrical or mechanical
drawing.
It is well known that blackboards have been made with vertically sliding
straight edges, but in such there is friction at either side and they are therefore
liable to jam or wabble, but with my horizontally sliding straight edge, the friction
is almost entirely on the lower guide and that as previously described has its lower
frictional surface largely reduced in area, so that a slight touch or push will send
the vertical straight edge from one end of the board to the other, thus overcoming
the above difficulty without the use of roller or ball bearings.
From the above description it will be seen that a very simple and convenient
portable blackboard has been devised well adapted for the use of teachers,
architects and draftsmen of all kinds.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed we declare that what we
claim is-
1. In an article of the class described the frame or easel comprising the feet A,
detachable standards B, provided with the supports S, and detachable cross
bar C, in combination with the blackboard D, resting on the supports S, and
provided with the loops E, adapted to fit over the upper ends of the standards,
substantially as and for the purpose specified.
2. In an article of the class described, the frame.or easel comprising the feet A,
detachable standards B, provided with the supports S, and detachable cross bar C,
in combination with the black board D, resting on the supports S, and provided
with the loops E, adapted to fit over the upper ends of the standards, and having
a vertical straight edge G, movable in guide-ways H, connected to the front of the
board, substantially as and for the purpose specified.
3. In an article of the class described, the frame or easel comprising the feet A,
the standards B; provided with the supports S, and with jaws a embracing the
feet A, and connected thereto by screws or pins, the cross-bar C, provided with
hooked lugs b engaging with the slotted plates I, connected to the sides of the
standards B, and overlying recesses therein, in combination with the blackboard D,
resting on the supports S, and provided with the loops E, adapted to fit over the
upper ends of the standards, substantially as and for the purpose specified.
4. In an article of the class described, a blackboard having horizontal guide-
ways formed thereon, in combination with a vertical straight edge adapted to slide
in the said guide-ways and provided with a scale, substantially as and for the
purpose specified.

page_text: 5. In an article of the class described, a blackboard having horizontal guide-
ways formed thereon, in combination with a vertical straight edge adapted to
slide in the said guide-ways and provided with a detachable scale, substantially as.
and for the purpose specified.
6. In an article of the class described, the blackboard D, having horizontal.
guide-ways H, connected thereto shaped in section substantially as shown, in.
combination with the heads J, adapted to slide in the guide-ways, the straight
edge G, connected to the heads and a scale K, sprung into the recesses c in the
heads J, and secured to the straight edge by the band screw L, substantially as.
and for the purpose specified.
this 20th day
Februar 1807
TONGUE & BIRKBECK,
Southampton Buildings, Chancery Lane, London, W.C.,.
Agents for the Applicants.