Improvements in and relating to Time Charts.
Year: 1893

page_text: Date of Application, 23rd May, 1893-Accepted, 1st July, 1893
COMPLETE SPECIFICATION.
Improvements in and relating to Time Charts.
I, ALEXANDER GLEASON, of 1201 Niagara Street, Buffalo, in the County of
Erie, and State of New York, United States of America, Designer and Engraver,
do hereby declare the nature of this invention and in what manner the same is to
be performed, to be particularly described and ascertained in and by the following
statement:
My invention has reference to certain mechanical devices and geographical
illustrations, to be used on a flat circular map of the world, and will be fully and
clearly hereinafter described and claimed, reference being had to the accompanying
drawings, in which :-
Fig. represents a flat circular map of the world, showing a plan of my
invention.
Fig. 2 is a sectional elevation through a central portion of the map.
A represents a flat circular map having twenty-four meridian lines, B, extending
from the center to the circumference. The periphery, C, of the circle being divided
into divisions, D, which represent the minutes in twenty-four hours; (for this purpose
it would take fourteen hundred and forty of these divisions) I have shown but half
of this number because the whole number would bring the lines too near together
for showing then clearly.
The twenty-four meridian lines are divided near the periphery each representing
quarters of an hour and at the periphery into 60 divisions each representing minutes
of meridian time.
A little way from the periphery at the twenty-four hour divisions, are the hours
of the day indicated by the letter, E, and commencing the reckoning of time from
Greenwich, London, on the line F.
On the face of the map toward the center is laid out the continents, principal
islands, rivers and cities of the world; their latitudes and longitudes corresponding
to all other first class geographical globe maps of the world.
On the face of the map are circular lines from the center or north pole to
90 degrees south representing the latitudes of the earth, north and south of the
equator.
These lines are indicated by G'.
In operating with this map I employ two indicating arms G and H, pivoted
together by means of a pin, a, having a flange, b, (see Fig. 2,) the two arms G
and H being put on said pin above the flange, b, then a light spring washer H', on
the top of the arm H and the head of the pin riveted so that the two arms are
held together by friction and can be turned on each other back and forth.
In the center of the map is an eyelet, c, and through the eyelet, c, is put the
lower end, d, of the pin, a, so that these indicating arms have two movements,
a movement one on the other and one or both together around the center of the
map, and may be detached at pleasure from the map if so desired, and are also
made removable by simply lifting the pin, d, out of the eyelet, c.
On these indicating arms are numerals J, indicating degrees of latitude corre-
sponding to the degrees of latitude as represented and marked on the inap at Bat
30 degrees west of Greenwich.
By bringing either of the indicator arms to any given point, the latitude and
longitude of the said point may at once be determined without computation.
In order to ascertain the time of day or
ponding to your own meridian time; first
he center socket or receptacle, letting the
your own meridian time, for instance if it
Price 27
night, in any part of the world, corre-
place the lower indicating arm, G, into
graduate edge of the arm be in line on
be New York, (the 15th meridian) and

page_text: you wish London's corresponding time place the arm H, on the meridian of
Greenwich, marked, F, at the same time holding the arm G in its place. You
have now got the absolute .corresponding difference of time between New York
and London, which is five hours in round numbers.
Next look at your own time and if it be eleven o'clock move the arm G to eleven
and the arm, H, will still retain its relative position to arm, C; (as the two arms
are held together, by friction) and indicate six p.m. or the corresponding fractional
parts of an hour be it more or less. Thus the time stands all ready computed to
any child who is able to read.
Again, in order to give the most simple lesson first, I would get the difference
of the time between the two places as above mentioned, then placing the arm G at
twelve, of course the arm G will stand at 5 p.m. for London, and there is no
computation or counting for the child to make; he thus, reads the hour and
fractional part thereof from the dial of the map. The utility of such a computating
map will be obvious, not only to the school child but for an adult or official person.
The map is not so extorted as to loose the relative latitude and longitude of any
places on the land or sea, but retains all latitudes and longitudes of places agreeing
with other recognized authors; and as the proper relations of continents and
countries all stand in their relative position to each other, they are thus impressed
upon the mind of the student.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed. I declare that what I
claim is:
The combination with a time chart, of a time dial encompassing the circular map,
a dial divided to indicate longitude and sun time on any meridian line, two
indicating arms loosely pivoted to the center of the map, numerals indicating
degrees of longitude on each arm, and a pivoted joint for holding said arms together
so the friction between them will hold them to the other at any point to which one
may be moved on the other and permit both to be moved together by turning one;
substantially as and for the purposes described.
Dated this 23rd day of May 1893.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.