Search Results for: Electro diagnostic apparatus
continuous sounds produced from pianoforte strings or springs, by means of currents of air which pass through apertures slightly wider than the body the air vibrates. aug. , w, southwell. spring applied to hammer butt, to obtain repetition. feb. , johann stumpff. improvements in mechanism and tuning apparatus
waddington. the ribs or bars ii front, instead of at the back, of the sounding board. may , . g. thomas. bracings dovetailed into the body of the wrest plank. may , j. harrison. metallic wrest plank and improved lever. aug. , w. s. smith. rounded bridges with plates of metal. oct. , . f. delsarte. apparatus...
https://www.piano-tuners.org/history/patents.html