The head of the stopper is fastened in a chuck and the peg is ground to the size of the mouth of the bottle by means of sand and water pressed against the glass by bent strips of thin sheet iron.
The mouth of the bottle is then pressed by hand on the peg of the stopper, and the mouth and peg are ground together with a medium of very fine emery and water until an air-tight joint is secured.
2) of a capacity varying from To to Too cc., fitted with an accurately ground stopper, which is vertically perforated by a fine hole.
For volatile liquids, a flask provided with a long neck which carries a graduation and is fitted with a well-ground stopper is recommended.
The top is fitted with a rubber stopper, or in some forms with a stop-cock, while a little way down there is a bent delivery tube (b).
To use the apparatus, the long tube is placed in a vapour bath (c) of the requisite temperature, and after the air within the tube is in equilibrium, the delivery tube is placed beneath the surface of the water in a pneumatic trough, the rubber stopper pushed home, and observation made as to whether any more air is being expelled.
The rubber stopper is removed and the experimental substance introduced, and the stopper quickly replaced to the same extent as before.
The vaporizing bulb A has fused about it a jacket B, provided with a condenser c. Two side tubes are fused on to the neck of A: the lower one leads to a mercury manometer M, and to the air by means of a cock C; the upper tube is provided with a rubber stopper through which a glass rod passes - this rod serves FIG.
To support the tube containing the substance to be experimented upon, and so avoids the objection to the practice of withdrawing the stopper of the tube, dropping the substance in, and reinserting the stopper.
The fundamental idea of Soxhlet's method for sterilizing milk is to boil it for forty minutes in small bottles holding just enough for one meal, and closing the same with an impervious stopper, which is only removed just before use.
Servants necessary for a pack include the huntsman, the duties of whose office a master sometimes fulfils himself; two whippers-in, an earth-stopper and often a kennel huntsman is also employed, thou h the 18th Lord Willoughby.
The earth-stopper "stops out" and "puts to" - the first expression signifying blocking, during the night, earths and drains to which foxes resort, the second performing the same duties in the morning so as to prevent the fox from getting to ground when he has been found.
In the interests of humanity care should be taken that the earth-stopper always has with him a small terrier, as it is often necessary to "stop-out" permanently; and unless a dog is run through the drain some unfortunate creature in it, a fox, cat or rabbit, may be imprisoned and starved to death.
A wooden stopper closes the mouth of the jar, and through lon.