The Gertz Tension Resonator

FROM THE MUSIC TRADE REVIEW, VOL 40, NO. 9, MARCH 4, 1905, PG 21

Secures Patent This Week Whereby the Tension on the Rim Supporting the Sounding Board of the Piano is Easily Adjusted and the Adjustment Maintained Regardless of Atmospheric Changes.

                        Washington D.C., March 1, 1905.

An improvement patent, bearing the No. 783,781, was this week issued by the Patent Office to Richard W. Gertz, of the Mason & Hamlin Co., Boston, Mass.  It relates to pianos, and has for its object to provide a novel construction whereby the tension of the rim supporting the sounding board may be easily adjusted and the adjustment maintained regardless of the hydrostatic changes in the atmosphere.

In patent No. 658,985, granted to Emil A. Gertz and R.W. Gertz, is illustrated and described a piano in which the rim to which  the sounding board is secured, as usual, is maintained at the proper tension by means of tension members, which pass through the rim and have suitable heads on their ends which engage the outside of the rim (outside of the inner rim – Vince).  The rim in said patent is constructed of a plurality of layers of wood placed with the grain running longitudinally thereof, and therefore the strain on the tension members is across the grain rather than in the direction of the length of the grain.

In order to keep the sounding board under proper tension, it is FREQUENTLY NECESSARY to tighten the tension members to such an extent that the heads on the ends of the tension members are apt to crush the grain of the wood against which they lie and to be drawn into the rim to some extent (Emphasis mine. We are told not to ever tighten those tension members).  The result is especially apt to occur whenever the rim swells any, due to moisture in the atmosphere or otherwise, for it is a well known fact that whenever wood swells or shrinks, the swelling or shrinkage takes place transversely to the grain rather than longitudinally thereof, and any swelling or shrinkage of the rim of the piano therefore causes it to increase or diminish in thickness or width.  Such increase or diminution in the thickness or width of the rim not only operates to increase or vary the tension on the tension members, but frequently causes the flat heads on the end thereof to become embedded in the rim.  As soon as this occurs the tension on the rim is reduced, and it becomes necessary to readjust the tension members (Again, my emphasis) in order to bring the sounding board up to its proper pitch.  It is to obviate this difficulty and to provide a construction in which the head on the end of the tension member will not become embedded in the wood of the rim under any circumstances that Mr. Gertz made his present invention.  This object is accomplished by providing the ends of the tension members with tapering heads, which are received in correspondingly shaped recesses in the rim.  The taper on the heads, while sufficient to prevent the latter from being pulled through the rim, is such that the strain on the tension members is transmitted to the wood substantially in a direction parallel to the direction of the grain of the wood.  With this construction the strain on the tension members will not crush the wood, as is the case where the pressure of the head comes transversely to the grain rather than longitudinally thereof, and therefore there is no danger of the heads becoming embedded in the rim and the tension on the latter relaxed due either to swelling of the rim or to any other cause.

END OF ARTICLE

So it appears that any Mason & Hamlin grand piano made prior to 1905 with the tension resonator present should be checked for tightness of the tension members, but those made after 1905 shouldn’t be. . .

What's real?

"Days pass and the years vanish

And we walk sightless among miracles.

Lord, fill our eyes with seeing.
Fill our minds with understanding.
Fill our hearts with pure intent.

Let there be moments when the holy ghost, like lightning,

Illuminates the darkness in which we walk.

Help us to see, wherever we gaze, that the bush burns, unconsumed.

And we, clay touched by God, will reach out for knowledge and exclaim in wonder,

How filled with awe is this place and we did not know it.”

- Anon.

Piano Moving in 1904

Moving pianos in large cities is a peculiar occupation. To the casual observer, it looks like a good, easy job for a strong, healthy man. There seems to be little to the business except tugging, pulling, pushing and lifting. Estimating the qualifications of a piano mover, one would be apt to demand of him little more than a broad, square pair of shoulders and sinewy arms capable of swinging several hundred pounds of dead-weight. That undoubtedly is the popular conception of the man who makes a success in this line. And it is not altogether a wrong conception for piano movers, as a class, are strapping big fellows with a generous gift of muscle.

But when you go to the bottom of their occupation you find that they must have other qualifications as well. It is a line of work which no one ever learns completely. A man may be an expert at moving pianos and yet every day encounter an angle to the business which will be absolutely new and which will call for the application of much mechanical ingenuity.

In days gone by, when flat buildings were designed and built with the comfort and convenience of their occupants as the dominating principle of construction, the piano mover had a comparatively easy life. In the first place, there were fewer pianos to move. He could devote more time to his work, and as there were few high apartment houses, each delivery was practically a repetition of the one preceding. Then came the modern flat building, with its winding, angular stairway, its narrow doorways and small windows, its elevated parlors and bewildering entrances. And with the advent of this modern building the troubles of the piano mover began to multiply, until today men engaged in this line of work are convinced that if they have any enemies they are to be found in the ranks of up-to-date architects. The designers of apartment buildings have increased the work of the piano mover fully fifty percent, and it is impossible to estimate the number of worries that have been heaped on his head.

Wherever it is practicable a piano is carried from the wagon to its resting place. Three muscular men will literally shoulder the instrument and plod up two, three of four flights of steps with the utmost ease. But where a stairway is too narrow to permit passage, or doors have been constructed on too cramped a plan, the piano mover must resort to other means of transportation.

The block and tackle is the favorite resource of the piano man when an instrument must be elevated from the outside, taken through a front window, or across the railing of a back porch. One end of the rope is hitched either to a chimney or some projection from an adjoining building and with muscular power the instrument is raised to any height desired and swung through an open window with the utmost care. In carrying pianos, the weight is divided between one man in front and two in the rear. Conditions frequently require that the keyboard and front of the instrument be taken off, and in rare cases it has been found necessary to reduce the piano to a skeleton before taking it into an apartment.

It is only within the last two years that the work of the piano mover became so fully developed that it called for the recognition of labor organizers. Up to that time almost any strong, healthy man with an aptitude for lifting could qualify as a piano mover. The intricacies of the work, however, began to multiply with the prevalence of the modern flat building, and the piano movers formed a union, which now has a membership of one hundred and fifty. It is a dangerous occupation, the number of injuries being great. As a rule, these injuries are sustained on stairways. - from "The Music Trade Review" pg. 35 vol. 39 no. 10, 1904.