(1) Equal parts of mutton rat and linseed-oil, mixed with 1/10 their weight of Venice turpentine, and melted together in an earthen pipkin, will produce a "dubbin " which is very efficacious in preserving leather when exposed to wet or snow, etc. It should be applied when the leather is quite dry and warm. (2) Many other formulae exist for dubbins, but all contain essentially the same ingredients. (3) A solution of 1 oz. solid paraffin in 1 pint light naphtha, to which 6 drops sweet-oil have been added, is put cold on the soles, until they will absorb no more. One dressing will do for the uppers. This process vastly increases the tensile strength of every stitch; and, while not removing the natural moisture of the leather, decidedly waterproofs the boot. A sole lasts 2 months longer when so treated. (4) There is nothing like castor-oil for preserving leather. Applied once a month, or once or twice a week in snowy weather, it not only keeps the leather-soft, but makes it waterproof. Copal varnish is the best thing to apply to the soles; but the latter should be thoroughly dry, and if they have been worn, they should be previously roughed on the surface before applying the varnish.
Linseed-oil is perhaps better than nothing, but it rots the leather; hence the objection to "dubbins " and other mix-ups of mutton-suet, linseed-oil, etc. The very best thing for waterproofing soles is Szerelmey's freestone liquid; 3 or 4 coats of this render the sole perfectly waterproof, and more durable With regard to castor-oil, it may further be said that it does not prevent a polish being produced on the boots, and that leather so treated is avoided by rats, if even its proportion be only 1/3 to 2/3 tallow. (5) Long-continued observation shows that harness and other leather exposed to the action of ammonia continually given off in stables, become weak and rotten sooner than ordinary leather. Even when care is taken to protect them with grease, this takes place. The addition of a small quantity of glycerine to the oil or fat employed in greasing such kind of leather has been recommended to keep it always pliable and soft.