6 ACID ACETIC. 



agency of these leaden vessels. Zinc, tin, and iron-tinned 

 vessels are not open to these objections ; and porcelain- 

 lined vessels have now mostly superseded bell-metal pre- 

 serving-kettles. 



Acids are still imperfectly known. The careful house- 

 wife knows that they are powerful agents, and to be used 

 with care. Fat, which retains its own in water, ether, and 

 alcohol, surrenders, by gradually decomposing, when strong 

 acids are applied to it. 



ACID ACETIC, OR VINEGAR, it is well known, is 

 made mostly from beer, wine, or cider, by exposing these 

 liquids to the atmosphere. 



A good vinegar for home consumption can be made by 

 mixing the weight of one part of strong brown sugar with 

 seven parts of water and a little yeast, putting the mixture 

 into a cask where the bung-hole shall be covered with a 

 bit of gauze or muslin, to keep out the insects. The cask 

 must be exposed to the sun and out-door atmosphere for 

 some weeks. 



A good cider vinegar is made by putting one pound of 

 white sugar to a gallon of cider, and allowing it to ferment 

 four months. 



French white-wine vinegar is much esteemed for domestic 

 purposes. 



The Vinaigre d'Orleans is made from the red wine of the 

 Orleannais. Vinegars called Champagne vinegars are often 

 made from red wines. 



The excise laws of England permit the use of free sul- 

 phuric acid to the amount of one part in one thousand, but it 

 is supposed that this amount is often increased. 



Vinegar can be thoroughly purified by distillation, as we 

 find it in the transparent distilled vinegar of commerce, 

 though still united with water. 



