How to Make Mechanical Crystal Chimes 



Tones produced by rubbing partially filled 

 drinking glasses with revolving wheels 



Bv J. S. Zerbe 



EVERY one is familiar with the musical 

 tones produced by gently rubbing the 

 fingers over the edge of a tumbler, the 

 neces5ar\- preparation for producing the 

 sound being moisture. The vibrator>' ac- 

 tion is greatly augmented by acidulating 

 the water, using the juice of a lemon, citric 

 acid or vinegar. 



The illustration shows a de\'ice which is 

 easily made, wherein a dozen or more 

 glasses can be used, the proper tone and 

 pitch of each being determined by the 

 amount of water which is carried in the 

 glass. The music from such a group is 

 exceedingly sweet and unlike that of any 

 other instru- 

 ment. The tones 

 are considerably 

 improved by 

 mounting the 

 mechanism on a 

 box, which thus 

 serves as a 

 sounding board. 



As herein 

 shown the base 

 is simply a 

 board, i6 in. 

 long, and 8 in. 

 wide, with a 

 post at the rear 

 corner of each 

 end on which is mounted a longitudinal bar, 

 the top being 6 in. from the base. Parallel 

 bars are placed 2 in. below the first one. 

 These are slightly separated from each 

 other, to receive between them the rear ends 

 of the lower members of U-shaped key-bars. 



The key-bars are made of soft steel 

 strips, each 14 in. long, 3^ in, wide and 1/16 

 in. thick. These are bent to assume a U- 

 form, the upper and the lower members 

 being parallel with each other. The rear 

 end of the upper member is secured to the 

 top of the longitudinal bar by means of two 

 screws, while the lower member rests be- 

 tween the two parallel bars mentioned. 

 On the forward ends of these key-bars are 

 mounted the keys for the musical scale, the 

 natural scale being preferable, which keys 

 are spaced equidistant from each other. 

 The keys representing C sharp, D sharp, 



Keys representing the natural scale are used and 

 clear musical tones are produced from the^ glasses 



F sharp, G sharp and A sharp are placed 

 between the keys thus indicated. 



Before the key-bars are put into position 

 two J^-in. holes are bored through each 

 member, one hole 2Y2 in. from their rear 

 ends, and the other 5 in. distant. These 

 holes ser\'e as bearings for spindles, each ot 

 which is 2 in. long. On the upper end of 

 each spindle is a grooved pulley, and on the 

 lower end a disk, a little less than half the 

 diameter of the top of a glass. On this 

 disk is strapped a thick rubber band, of the 

 kind which is wider than the thickness of 

 the disk, so as to form a receptacle for hold- 

 ing water on top 

 of the disk when 

 it is in position. 

 An endless belt 

 passes along the 

 two trains of 

 pulleys, starting 

 from a power 

 pulley which is 

 operated by a 

 crank. An idler 

 pulley at the op- 

 posi te end , 

 which is capable 

 of being moved 

 a limited dis- 

 tance, ser\es as 

 a tightener for 

 the belt by which adjustments are made. 

 The tumblers used are of thin white glass, 

 and these are arranged below the spindles 

 so that a disk is within each glass, but 

 fully 3^ in. from the rim at the rear side 

 of the glass. In that position a downward 

 pressure on the key will cause the lower 

 member of the key-bar to move to the rear, 

 through its bearing, and thus bring the 

 rotating rubber-tired disk against the inner 

 edge of the glass. In mounting the glasses 

 on the board they can be securely held by 

 a coating of thick gum tragacanth. 



Water is put into the various glasses, and 

 more or less added until the proper musical 

 pitches are obtained. A mark is then 

 placed in the side of each glass so that 

 there will be no trouble in refilling them to 

 get the correct tones. The disks may be 

 turned by a motor or by an assistant. 



447 



