Prague’s zinc slate
Author: Václav Malý, a teacher in Klar’s Institute in Prague
The year of production of the first slate: 1886
Dimensions: 33 x 24 cm
Donor: The Blind Museum in Levoča and Elementary School for the Blind in Levoča
Prague’s slate was produced in 1886 at Klar’s Institute in Prague. Its inventor was Václav Malý, the teacher. A 21-line, two metal sheet slate was used by the blind for writing in Braille. Over time, slates with less lines and plastic ones were produced. The blind were using a stylus consisted of a metal pin and a handle for embossing.
A metal pin is 0,8 – 1 cm long and its tip has a parabolical shape. A diameter of the pin is approximately 1 mm and it corresponds to a diameter of a relief dot and to thickness of paper. The handle is usually wooden or plastic, the most frequent is pear-shaped. Pressing the stylus against slate makes an identation on the paper that is possible to read by touch on the opposite side after taking the paper out from the slate. It is necessary to punch dots from right to left on the slate (negative) so they can be read from left to right (positive).