CLEANING BOTTLES The methods employed for cleaning bottles will depend upon what the bottles have contained. The simple and old-fashioned method of half filling the bottle with water and adding sand, cinders, or shot may serve in some cases, as may the use of a little vinegar and broken-up egg-shell. Generally, however, the best bottle cleaning solution is one made in the proportion of from 2 oz. to 4 oz. of hydrochloric acid to one pint of water. This mixture is allowed to remain for a time in the bottle, shaken frequently, poured into another one, and the bottle rinsed well with clean water. Bottles that have contained oil should be rinsed first with a strong solution of household washing soda, caustic soda or potash, or liquor ammonia, and finally with weak hydro chloric acid. Commercial benzole may also be used for greasy bottles, followed by a strong solution of washing soda, finally rinsing with plenty of water.
Bottles which have been used for varnish may be cleaned by rinsing with liquor ammonia part, methylated spirit so parts, and finally with weak ammonia and water. It is better to use liquid than mechanical cleaners (sand, shot, etc.), which are apt to roughen the insides of the bottles, such roughness causing them to become dirty and unsightly very quickly. Bottles used for gold toning solutions quickly become dirty owing to the gold depositing itself upon the inside of the bottle ; if the deposit is not removed the gold in fresh solutions will be attracted by it, to the detriment of the solu tions. Weak hydrochloric acid should be used as a cleaner for such bottles, and if this fails aqua regia should be used.