TURPENTINE. 9 
it to dissolve slowly to a jelly. When glue prepared in this way is 
put on to heat the next morning it dissolves in the water rapidly 
and smoothly, and has the further advantage of being somewhat 
stronger than that which is simply mixed with cold or hot water 
and immediately heated. 
‘8 Since animal glue rapidly loses its adhesive strength when it is 
subjected to a high temperature, it never should be boiled. Glue 
prepared in a single unjacketed kettle over an open fire will almost 
certainly become too hot and boil when not watched, or it will not 
be hot enough to properly glue the barrels without waste. In pre- 
paring the glue, then, use a double boiler or jacketed glue kettle. 
The boiling water in the lower pot heats the glue in the upper pot to 
the proper temperature without bringing it to a boil. Do not keep 
the glue hot longer than necessary. Have the barrels ready to glue 
as soon as the glue is hot, glue at once, and clean the glue kettle for 
the next day. 
Before glueing the barrel, drive the hoops down moderately tight. 
Then pour about 1 gallon of the hot glue into the barrel, plug up the 
bunghole, and sluice the barrel around well, making sure that the 
glue comes into contact with every bit of the inside surface. Remove 
the stopper, place the barrel on a rack over the glue kettle, and allow 
the excess glue to drain directiy into the kettle. As soon as most 
of the excess glue has drained out, take the barrel from the rack, and 
stand it on one head in a level place. About one-half hour later, 
drive the hoops down absolutely tight, so that the tension on the 
hoops all around the barrel will be equal, and let it stand on the same 
head, thus permitting some of the soft glue still inside the barrel to - 
settle down in the chine where most of the leaks occur. Allow the 
» barrel to stand, bung open, for several days under a shed, protected 
from the sun and rain, and then glue again exactly as before, but 
making sure that the barrel stands on the other head this time. 
After two days the barrel is ready for use. Barrels glued in this 
way should give httle, if any, trouble from leaking, provided no water 
is allowed to get in. 
As animal glue is extremely subject to decomposition through the 
action of bacteria and molds from the air, glue left in an open kettle 
soon begins to decompose, as shown by its foul odor, thus becoming 
no longer fit for use. It is, therefore, highly important to keep any 
left-over glue sweet and clean if it is to be used again. The unused 
glue should be poured into a can which may be tightly covered and 
‘® stored in a cool place, and the pot thoroughly cleaned. Fresh glue 
is ruined if put in a filthy pot, containing decomposed, foul-smelling 
material. The purpose of the borax recommended in the formula 
on page 8 is to help keep the glue sweet, and it should be dissolved 
in the glue when ready for use. 
474°—20——2 
