1851 Great Exhibition: Official Catalogue: Class X.: W. Mathews
550 MATHEWS, W., 5 St. James Street, Nottingham - Inventor and Manufacturer.
Model, exhibiting the string frame of an upright pianoforte with lever tuning apparatus; the object being to sustain the pressure of the strings, and prevent the instrument getting out of tune.
An upright pianoforte, in which an apparatus is introduced to keep the instrument in its upright position. It is also simple in action, and contains an apparatus whereby various degrees in quality of tone may be produced.