PACIFIC SALMON FISHERIES. 129 
shipped to foreign countries with less fastidious tastes in the mnatter 
of salmon. In 1910 one of the leading companies of Alaska adopted 
the policy of throwing overboard all ‘‘do-overs.”’ 
On coming from the second retort the coolers are lowered into a 
bath of lye, or, as in some canneries, the cans are run through such a 
bath on an endless belt, which, with the aid of a slight rinsing and a 
few rubs with a brush over the top, removes from the can all the 
grease and other material. The belt then passes them into another 
bath where the lye is washed off in hot fresh water. The cans then 
go to the cooling room, where a stream of water is played upon them, 
or, during rainy weather are placed out of doors upon the wharf, and 
there allowed to cool. 
The top and bottom of the cans contract in cooling, and for several 
hours a sharp popping noise is heard. Here, as in nearly every proc- 
ess through which they pass, the cans are again tested, this time by 
tapping the tops with a small piece of iron about 6 inches long, or, 
sometimes, a 12-penny nail. The sound conveys to the ear of the 
tester an unmistakable meaning as to the condition of the can, and 
the faulty cans that escape notice during the other tests are almost 
invariably found in this one. 
LACQUERING. 
An almost universal custom in the salmon-canning industry, but 
one that is not common in the canning of vegetables, fruits, etc., is 
that of lacquering the cans. This idea of protecting the can on the 
outside has been followed from the very beginning, for two reasons: 
(1) That the English market which, at that time especially, absorbed 
the greater part of these goods, insisted on their shipments being 
finished in this way, and (2) from the fact, as these canners speedily 
found out, that if they did not protect their cans in some way enor- 
mous losses through rust would ensue. 
The first experiment of this nature was to paint the cans by hand 
with red paint, treating each singly. Next a composition of logwood 
extract and alcohol was tried, which, however, did not produce satis- 
factory results for a very plain reason—the can was dyed instead of 
being lacquered. The next attempt was to varnish the cans with a 
japan varnish reduced with alcohol, but this was found to dry too 
slowly for speedy handling. After extended experimentation the 
quick-drying brown lacquer of the present time was evolved, which 
carries asphaltum in the form of an asphalt varnish as its base, this 
being supplanted in some cases by gilsonite. This lacquer can be pro- 
cured in either a heavy or light body, is generally reduced with ben- 
zine or gasoline, and is applied according to the requirements of the 
market, which in some localities demands a heavy coating and in 
