US98320A - Improvement in sun-dials - Google Patents

Description

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' Letters Patent No. 98,320, dated December 2,8,1869- IMPRQVEMENT IN SUN-DIALS.

The Schedule referred to in these Letters Patent and making part of the same.

To all whom it may concern Be it known that I, LUDWIG IGNATIUS TRUEG, O. S. B., of St. Vincente, in the count-y ot Westmore-y land, and State oflennsylvanin, have invented a. new and improved Sun-Dial; and I do hereby declare that the following is a full, clear, and exact description thereof', which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawing, formingr part of this specification, in which- Figure 1 represents a vertical transverse section of my improved sun-dial.

Figure 2 is a back View of the same.

Figure 3 is a plan or top view of the'same.

Similar letters oi' reference indicate corresponding parts.

This invention relates to sun-dials; and

lt consists in a novel arrangement and construction of parts, as hereinafter specified.

A, in the drawing, represents a plate or disk, made of wood or other suitable material.

Upon it is pivoted another plate, B, by a vertical pin, a. v

From the plat-eB project two vertical posts, C C, to which are secured the ends of a sheet-metal arc, D. The ends ot' this arc,'and the middle of the same, are equidistant from' the pivot a. y

The inner face. of thc. are is graduated, to indicate In line between the pivot and the middle of thearc isfastened, upon the platform A, a vertical plate', E, made inform of a quadrant, and extending, with its front edge, close to the are.

The plate E projects through a slot of the plate B, to remain stationary with the plate A, while the are may he turned with B, or 'vice versa.

The ends vof the are lhave curved slots, through which'the pins b, that tasten the are tothe posts, are tted. The are can thus be not only swung on its pivots b, but can also be so set thereon that its inner face is always parallel with the ti'ont edge ot' E. y

A compass, F, is secured upon the plate B, with its centre in line with the pivot a and plate E. The device is used in the following manner:

It is set up, with the plate E in line with the'needle of the compass, and with the middle of the arc also in line with the same. The arc is then set at a degree corresponding to the degree of latitude in which the device is set up.

To facilitate this adjustment, figures may be marked near the slots at the ends ofthe are. the plate E falling upon the are, will denote thereon the correct time. Butas the clock time varies more or less from the true time shown by the sun, the are may be shifted sideways on the pivot a, to let the shadow indicate the regular clock time.

The plate E is made so much larger than a quadf rant as to add, with the thus enlarged shadow, the time apparently lost by our inability to perceive the sun in the exact position which it occupies.

H Having thus described my invention,

I claim as new, and desire to secure by Letters Pate-nt- The graduated are D, provided with slotted ends, in combination with thequadraut or gnomon E, and pivoted plate B, as shown and described.

LUDWIG IGNATIUS TRUEG, O. S. B.y

Witnesses:

Guo. W. MABEE, ALFRED Lvneo'rcr.

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