Library Collections: Document: Full Text

UNITED STATES PATENT OFFICE.

GEOEGE A. MANSFIELD, OF MELROSE, MASSACHUSETTS.

IMPROVEMENT IN CHAIRS FOR INVALIDS.

Specification forming part of Letters Patent No. 39,663, dated August 25, 1863; antedated December 21, 1861.

To all whom, it may concern:

Be it known that I, GEORGE A. MANSFIELD, of Melrose, county of Middlesex, and State of Massachusetts, have invented a new and useful physiological improvement in the form and construction of chairs, whereby they are adapted to the care and prevention of consumption and other diseases of the chest, the great advantages of which I have already proven; and I do hereby declare that the following description, with the accompanying drawings, forms a full, clear, and exact specification thereof.

My improvement is in the upright support or "back" of the chairs, as it is termed. In nearly all chairs or seats of every kind the back is either flat or circular by an inward curve, in either of which cases there is a constant tendency to force the shoulder-blades forward and compress the chest. The drawings represent one of my improved chairs, adapted to obviate this objection.

Figure 1 is a side view of the chair. Fig. 2 is a horizontal cross-section on line A B of Fig. 1, showing also by red lines (for illustration) the outline section through the chest of a person sitting in the chair.

On the front part of the back of the chair I construct a protuberant projection, a, of several inches in length, and of sufficient projection and of such limited width as to pass in between the shoulder-blades b, (red,) and support the dorsal column c (red) of the patient. I make the dorsal supporter a of any suitable material, of such limited elasticity and softness as not to irritate the patient's back, and I either construct the same homogeneously with the back of the chair or make it separately, and affix the same in any convenient method to the back of the chair as a distinct fixture.

For school-chairs and some other situations where appearance is not of consequence, my principle may be attained in a degree by making the back of the chair of such limited width as to pass completely in between the shoulder-blades and leave their backward movement free.

I claim --

The dorsal supporter a, constructed wither applied to the back of a chair, substantially as described, and specifically for the objects and purposes set forth.

GEO. A. MANSFIELD.

Witnesses:
LUTHER BRIGGS, Jr.,
BENJ. P. CHNADLER.