PROCEEDINGS X)F THE POLYTECHNIC ASSOCIATION. 537 



spruce wood has little red streaks in it, and some manufacturers think the 

 larger these streaks the finer the tone, but he thought the smaller the 

 streaks the better the tone. Some contend that the tone is increased 

 between these streaks. Various metals have been tried for sounding 

 boards, and even glass, but it was found that metals always destroyed the 

 sound or tone. Our main guide is the violin sounding board. The style 

 most made in this country is the square piano. Ninety-eight out of every 

 hundred are of this kind. The square piano is used for a large room, 

 and the upright for a small room. The strings in each are precisely alike, 

 but the action of striking is different. A greater power can be exerted 

 upon the horizontal than upon the upright piano strings. The action most 

 used by makers in New York is called the French grand action. 



The piano keys are balanced with lead so as to make each end precisely 

 of the same weight. If this is not done the key will not respond readily 

 to the touch. There is no rule laid down for makers to go by. Each 

 establishment has its own system or scale to which all its pianos conform. 

 It is surprising, however, to hear the great diversity of opinion expressed 

 by professors and experts regarding the tone of the same piano. There is 

 no book to give instruction regarding the manner of producing uniformity 

 of tone by the arrangement of the woodwork. The art is attained by a 

 few workmen who, as a general rule, are not piano playei's, and therefore 

 take the opinion of professors as to the quality of tone produced. 



Adjourned to March 23d. 



'■} 



American Institute Polytechnic Association, 

 March 23, 1865. 



Prof. S. D. Tillman in the Chair; Mr. B. Garvey, Secretary. 



The Chairman said he would substitute for his usual budget of scientific 

 intelligence, an article by him, lately published in Humphrey's Journal of 

 Photography : 



Clydonics — No. 1. 



BY PROF. S. D. TILLMAN. 



Read before the American Photographical Society. 



Under this title, derived from the Greek, Kludon, it is proposed to embrace 

 those branches of science which treat of waves and undulations; of oscil- 

 lations, vibrations and pulsations. By grouping in this manner, manifes- 

 tations of force through to and fro motions, more or less rapid, the student 

 is enabled to view this class of reactions from a stand-point where com- 

 parative measurements and estimates greatly assist him in reaching and 

 retaining correct conchisions. All the notes in Nature's harmony, heard 

 and unheard, thus become a part of one grand gamut, extending from the 

 profound sub-base of the great tidal wave, having a single diurnal culmi- 

 nation, upward through the diapasons of sound and color, to the very 

 altissimo of the tremulous aith, whose waves — quicker than thoiiglit — 

 generate a pitch far higher than the violent tone, and, being beyond the 



