This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
A requisite for bottling is a test gauge. This is an instrument for ascertaining the pressure of gas in the bottles filled with carbonated waters, after they are corked, in order to check the work of the bottlers, and also to test the beverages of different makers. By this gauge an employer has it in his power to ascertain if the bottler is keeping correct pressure in the bottles, also to see if the same class of drinks are alike. It is easily attached to a bottle by a screw for penetrating the cork, provided with a small cock and union.
Fig. 257. - Testing Gauge for Corked Bottles.
Fig. 258. - Testing Gauge for Patent Stopper Bottles.
The gauge is used in the following manner: - To test a bottle, first insert the point on the end of the screw to penetrate the cork for the screw to follow, pass the screw entirely through the cork, and the point will fall out to the bottom of the bottle, leaving the passage through the cork clear; attach the gauge by the small union and turn the cock, to let the pressure into the gauge. Thirty-five to fifty lbs. is a good general average pressure for all beverages.
Fig. 258 is a device for being attached to the above pressure gauge and used when testing the pressure in patent bottles. The under part of the tongs is shaped like a fork: this is placed under the ring or neck of the bottle, when, by compressing the handle, the plug on upper part will be brought on to the top of the stopper in the bottle, and so force it away from its seat the pressure can now be noted, and by reversing the 23 bottle the tongs can "be taken off, the stopper will take its seat, and the bottle be again closed.