During the season of 1846 I played the pianoforte part throughout the series of six concerts of chamber-music given by the Harvard Musical Association. I remember that Mr. Blessner played the violin and Mr. Groenvelt the violoncello, but cannot recall the names of the players of the second violin and viola. These concerts were given at the pianoforte warerooms of Mr. Jonas Chickering, 334 Washington street, Boston. I still have the programs. String quartets by Haydn, Mozart, and Beethoven were played, also piano trios by Beethoven, Reissiger, and Mayseder. LEOPOLD DE MEYER The knowledge I gained from Mr. Schmidt was largely advanced and supplemented by what I learned a year or two later, in 1847-48, from the playing of the pianoforte virtuoso Leopold de Meyer, who came to the United States about that time. It was from a careful study of the manner of his playing that I first acquired the habit of fully devitalized upper-arm muscles in pianoforte-playing. The loveliness and charming musical beauty of his tones, the product of these conditions, greatly excited my admiration and fascinated me. I never missed an opportunity of hearing him play, and closely watched his movements, and particularly the motions of hand, arm, and shoulder. I was incessantly at the pianoforte trying to produce the same delightful tone quality by imitating his manner and style. [Illustration: WILLIAM MASON AT THE AGE OF EIGHTEEN FROM A DAGUERREOTYPE ] My continued perseverance was rewarded with success, for the result was a habit of devitalized muscular action in such degree that I could practically play all day without a feeling of fatigue. The constant alternation between devitalization and reconstruction keeps the muscles always fresh for their work and enables the player to rest while playing. The force is so distributed that each and every muscle has ample opportunity to rest while yet in a state of activity. Furthermore the tones resulting from this touch are sonorous and full of energy and life. An idea of my own which was persistently carried into act aided materially in bringing about the desired result. This was to allow the arms to hang limp by my side, either in a sitting or standing posture, and then to shake them rigorously with the utmost possible looseness and devitalization. This device was in after years recommended to my pupils, and those who persistently followed it up and persevered for a while gained great advantage from it, and eventually acquired a state of habitual muscular elasticity and flexibility. I might easily have learned from any book of anatomy the names of the muscles which are here referred to, but for the practical instruction of pianoforte pupils this seemed to be of little consequence. However, there are three muscles of the upper arm which may here be named: the triceps, the brachialis anticus, and the biceps. Of these the first-named is of the most importance to the pianist.