The safety of glass articles packed together in a box does not depend so much upon the quantity of packing material used, as upon the fact that no two pieces of glass come into actual contact. In packing plates, a single straw placed between two of them will prevent them from breaking each other. In packing bottles in a case, such as the collecting case of the microscopist, and the test ease of the chemist, rubber rings, slipped over each, will be found the best and handiest packing material. They have this great advantage, that they do not give rise to dust.
One of the most important things is to season glass and china to sudden change of temperature, so that they will remain sound after exposure to sudden heat and cold. This is best done by placing the articles in cold water, which must gradually be brought to boiling, and allowed to cool very slowly, taking several hours. The commoner the materials, the more care is required. The best glass and china are well seasoned before sold. Such wares may be washed in boiling water without fear of fracture, except in frosty weather, when, even with the best, care must be taken not to place them suddenly in too hot water. China that has any gilding may on no account be rubbed with a cloth of any kind, but merely rinsed first in hot and afterwards in cold water, and then left to drain till dry. If the gilding is very dull and requires polishing, it may now and then be rubbed with a soft wash-leather and a little dry whiting; but this must not be more than once a year, or the gold will be rubbed off and the china spoilt. When put away in the china closet, pieces of paper should be placed between them to prevent scratches on the glaze or painting, as the bottom of all ware has little particles of sand adhering to it, picked up from the oven wherein it was glazed.
The china closet should be in a dry situation, as a damp closet will soon tarnish the gilding of the best crockery. In a common dinner service, it is a great evil to make the plates too hot, as it invariably cracks the glaze on the surface, if not the plate itself. We all know the result - it comes apart. The fact is, when the glaze is injured, every time the "things" are washed the water gets to the interior, swells the porous clay, and makes the whole fabric rotten. In this condition they will also absorb grease, and, when exposed to further heat, the grease makes the dishes brown and discoloured. If an old, ill-used dish be made very hot indeed, a teaspoonful of fat will be seen to exude from the minute fissures upon its surface. These latter remarks apply more particularly to common wares. As a rule, warm water and a soft cloth are all that is required to keep glass in good condition; but water-bottles and wine decanters, in order to keep them bright, must be rinsed out with a little muriatic acid, which is the best substance for removing the "fur" which collects in them. This acid is far better than ashes, sand, or shot; for the ashes and sand scratch the glass, and if any shot is left in by accident the lead is poisonous.
Richly cut glass must be cleaned and polished with a soft brush, upon which a very little fine chalk or whiting is put; by this means, the lustre and brilliancy are preserved. (Boston Journal of Chem.)