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Popular Science MoniltJii 



T 



The current of water through the vibrator is in- 

 terrupted ten times a second with this apparatus 



Making the Water from a Faucet Vi- 

 brate Fifteen Times a Second 



IF water fnjin a water-supply conduit 

 is introduced under pressure in the 

 outer space, or tulie, of a df)uble cyl- 

 inder perforated with fine holes at its 

 rear end, the water is forced to flow 

 out through the fine holes. If a rubber 

 membrane is stretched across the holes 

 ii will vibrate because of the repeat'- I 

 u[)war(l pressure of the outtlowing water 

 and the alternate action of auction. 

 The illustration shows a \ ibration 

 ai)paratus embodying the principk' 

 of an interrujiter in which the stress 

 transmitted upon the rubber mem- 

 brane is obtained in a simple manner. 

 In a metal screw-ring is a rubber 

 membrane antl below it is a rub- 

 ber ring. When the metal ring is 

 screwed upon the lo|) part the rub- 

 ber membrane is stretihed acro.ss 

 the cone, and on opening the water 

 cock it is subjected to rapid vibra- 

 tions. In case the vibrations of the 

 membrane are to be transmit tetl tu 

 a piston, the ring is removed b\' un- 

 screwing and a fixture is usi-d 

 instead. Tiiis consists of thi- >ame 

 met.il ring antl in addition a pi>ton 

 hclil inider ti-nsion by means of ,i 

 s|)ring in the cylinder. When tlu- 

 membrane is subjected to tin- iip- 

 .md-down movement it pushes the 

 |)iston upward. The piston is then 



depressed b\- the spring and again driven 

 u[)ward by the membrane. 



One peculiarity of the water-pressure in- 

 terrupter is that in the expulsi<jn of water 

 ten to fifteen interruptions of the current 

 occur e\'ery second, instead of a constant 

 Hovs'. For instance, if the out-flowing 

 water is directed into a bottle the water 

 ( urrent issuing jerkiK- will act more 

 eflectiveK" in cleaning the bottle than 

 would the ordinary flowing current nt 

 water. 



Saving Gold and Silver on the 

 Vacuum- Cleaner Principle 



STAR 11. IXC amounts of metal ar* 

 remo\ed from gold and silver arti- 

 cles b\' the simple work of polishing. In 

 the case of jewelers who do much polish- 

 ing work during a year, the loss in gold 

 and silver is great. 



.■\ new form of polishing-machine aims 

 to conserve the dust by means of a 

 suction-fan mounted 

 near the rajiiiUy re- 

 xoK'ing brushes. The 

 dust which ihes oft of 

 the wheels is drawn 

 d(jwn into a series of 

 traps, from which it 

 may later be removed 

 ;ind assayed for the 

 pure metal. 



^^. 



A suction l;in on a jeweler's polisliing macliinc 

 draws all the gold and silver dust into a trap 



