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AUTOMATIC SAFETY-VALVE STOPPER. 
peroxide of hydrogen, has devised an ingenious stopper which 
he calls the “automatic safety valve rubber cork,” and which is 
shown in the illustration. 
The material of the stopper is vulcanized rubber. The 
beveled end is punctured through in such a manner that when 
the pressure in the bottle rises above 5 to 8 pounds to the square 
inch (according to the thickness of the rubber at the bottom, 
which may vary slightly), the excess of free oxygen finds free 
eofress and thus relieves the tension. 
o 
(a) Puncture. 
Cut No. 2. Illustrates the cross 
section of a bottle corked and 
capped with vegetable parchment 
and parafined muslin ; no wire. 
This device is first inserted, and a plug of porous wood is 
then driven in, thus stiffening the rubber and completing the 
operation of “corking.” 
The capping consists of vegetable parchment covered with 
parafined muslin, no wiring being used or needed. 
It is easily seen that this style of closing the bottle obviates 
the possibility of bursting. Assuming even, that through some 
imperfection of the stopper, the puncture should close, as soon 
as the pressure rises to a point far within that required for rup¬ 
ture of the bottle, the stopper, not being wired down, will yield 
and be forced out. 
Retail druggist who have for so many years been the chief 
sufferers and losers from the bursting of the peroxide containers, 
and the deterioration of the substance otherwise from the causes 
indicated above, will welcome Mr. Marchand’s invention as a 
happy solution of what has to them been a very serious problem 
