Impervious Corks

Corks which have been steeped in petrolatum are said to be an excellent substitute for glass stoppers. Acid in no way affects them and chemical fumes do not cause decay in them, neither do they become fixed by a blow or long disuse.

Non-Porous Corks

For benzine, turpentine, and varnish cans, immerse the corks in hot melted paraffine. Keep them under about 5 minutes; hold them down with a piece of wire screen cut to fit the dish in which you melt the paraffine. When taken out lay them on a screen till cool. Cheap corks can in this way be made gas- and air-tight, and can be cut and bored with ease.

Substitute for Cork

Wood pulp or other ligneous material may be treated to imitate cork. For the success of the composition it is necessary that the constituents be mingled and treated under special conditions. The volumetric proportions in which these constituents combine with the best results are the following: Wood pulp, 3 parts; cornstalk pith, 1 part; gelatin, 1 part; glycerine, 1 part; water, 4 parts; 20 per cent formic-aldehyde solution, 1 part; but the proportions may be varied. After disintegrating the ligneous substances, and while these are in a moist and hot condition they are mingled with the solution of gelatin, glycerine, and water. The mass is stirred thoroughly so as to obtain a homogeneous mixture. The excess of moisture is removed. As a last operation the formic aldehyde is introduced, and the mass is left to coagulate in this solution. The formic aldenyde renders the product insoluble in nearly all liquids. So it is in this last operation that it is necessary to be careful in producing the composition properly. When the operation is terminated the substance is submitted to pressure during its coagulation, either by molding it at once into a desired form, or into a mass which is afterwards converted into the finished product.

To Clean Corks

See Cleaning Preparations and Methods, under Miscellaneous Methods.

CORK TO METAL, FASTENING: See Adhesives, under Pastes.

CORK AS A PRESERVATIVE

See Preserving.

CORKS, WATERPROOFING

See Waterproofing.