The Winter Food Supply 245 



sale, as blue or green glass detracts from the appear- 

 ance of the contents. Wide-mouthed jars are best for 

 packing whole products and are easiest to clean. Small- 

 necked bottles can be used for fruit juices. Large- 

 mouthed bottles can be used for jams, marmalades and 

 jellies. 



Jars should be tested before they are used. Some 

 of the important tests are here given : 



1. When using glass-top jars, first examine for 

 cracks ; then run a finger around the edge of necks of 

 jars, and if there are sharp projections, file them off, or 

 scrape them off with an old knife. If left on, they may 

 cut rubbers and interfere with perfect sealing. Place 

 a top on a jar. It will slip from side to side, but should 

 not rock, when tapped. Rocking tops will not make a 

 tight seal. Sometimes the fault is with the top and 

 sometimes with the neck. Defective jars and tops when 

 discarded for canning purposes may be used as con- 

 tainers for jams, etc. The top bail should go into posi- 

 tion with a light snap. If too loose, it should be taken 

 off and bent slightly inward in the center. If too tight, 

 bend outward. 



2. In screw-top jars, only the lacquered or vulcanized 

 tops should be employed. Screw the top on tightly 

 without the rubber. If the tip of a knife or fingernail 

 can be inserted under the rim the tops should not be 

 used for cold-pack canning. If the defect is very slight, 

 however, it may be remedied by pressing a knife handle 

 on the lower edge against a hard surface, thus straight- 

 ening the offending bulge. Another test is made by put- 

 ting on the rubber, screwing the top on tightly, and 

 then pulling the rubber out. If the rubber returns to 



