US 413147 A
Description (OCR text may contain errors)
(No Model.) I C. 1-1. PERRY.
, BLACK TABLET.
No. 413,147; Patented Oct. 15, 1889.
(Fcmlesllfeyzy, JZ;/a @M Nv PETERS Photo-Lithographer, Wahingtun, 11c) UNITED STATES PATENT OFFICE.
CHARLES E. PERRY, OF BOSTON, ASSIGNOR OF ONE-HALF TO HOBART M. CABLE, OF HYDE PARK, MASSACHUSETTS.
SPECIFICATION forming part of Letters Patent No. 413,147, dated October 15, 1889. Application filed January 22, 1889. Serial No. 297,192. (No model.)
To aZZ whom it may concern:
Be it known that I, CHARLES E. PERRY, of Boston, county of Suffolk, State of Massachusetts, have invented an Improvement in Black Tablets, of which the following description, in connection with the accompany ing drawings, is a specification, like letters on the drawings representing like parts.
Prior to my invention letter and white paper have been collected in block form, to be written upon by a lead-pencil and by ink on a pen. In the use of the block referred to the obliteration of a lead-pencil mark necessitates much rubbing of india-rubber on the paper, and to obliterate the ink mark an eraser, usually of steel, is used. In either case time is wasted, and the erasure commonly shows, and it is customary to use a sheet but once when the sheet is wasted. School -children commonly use slates, which are marked upon by slate-pencils, the mark being readily removable by a damp cloth or sponge, and in schools boards of wood painted black are written upon by chalk, and a sponge or rag is employed to remove the chalk.
My invention has for its object the production of a novel black tablet to take the place of slates and blackboards in schools and other places where such articles are used.
To accomplish my invention effectually and yet cheaply and neatly, I have devised a black tablet adapted to be marked or written upon by a slate-pencil of usual construction, the mark being as easily obliterated, when desired, as the mark of a slate-pencil on a slate.
The paper employed by me for the tablet contains lamp-black or other usual blackcoloring-matter, which may be readily and legibly marked by means of a slate-pencil, leaving the mark readily removable by the use of a dry cloth, so that the black surface may be used over and over again, as the surface of a slate or black tablet.
My invention consists, essentially, in a black tablet composed of numerous sheets of made to represent a blackboard, and Fig. 3 a
section of Fig. 1..
In the production of my improved tablet I take a suitable number of sheets of heavy black paper containing lamp-black or other equivalent black coloring agent, which will leave a surface capable of being marked by a slate-pencil to leave a white or whitish mark, which may be readily removed by a dry rag, leaving the surface free and clean, to be again marked. These black sheets are superimposed in a pile a to form a tablet of the required thickness, and in such condition are, with a stiffening or back piece I), united or bound together, as at c c, Fig. 1, along two edges, or, as in Fig. 2, about all the edges. These sheets after considerable use, or when desired, may be torn off one by one.
My improved black tablet possesses to my mind many advantages over usual slates, because of lightness and greater strength, the tablet being the lighter of the two in weight and neater in use.
I do not profess to bethe inventor of black paper, per se; but I am not aware that any one prior to my invention thereof has ever conceived the invention of a tablet composed of black paper to be employed as a substitute for white paper and painted wooden board. I
I am aware that thin tissue, manifolding, or carbon papers have heretofore been made up into tablets provided with covers to avoid soiling the hands; but such carbon papers do not have surfaces adapted to be written on by a white pencil, as the carbon is in-v As an improved article of manufacture, In testimonywhereofIhave signed my name the herein-described black tablet, composed to this specification in the presence of two subto of superimposed sheets of heavy black pascribing Witnesses. per with a hard-finished surface adapted to be marked on by a pencil and the marks CHARLES E. PERRY. erased Without injury thereto, said sheets Witnesses: being secured together and united to a back, BERNIOE J. NOYEs,
substantially as described. GEO. W. GREGORY.