234 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
removal of the viscera after the capture of the fish; (b) the careful handling of the 
fish, both before and after evisceration; (c) the thoroughness with which the walls of 
the abdomen are washed, and (d) the care with which the fish are packed. The use 
of boric acid will not prove satisfactory if fish are first thrown about, walked upon, 
carelessly eviscerated, washed in the sterilizing fluid, and then pitched into barrels. 
Those who prefer to abuse fish in this way will do well to stand by the older and more 
expensive methods — use ice, and complain of the market. 
Mr. E. G. Blackford, one of the largest wholesale dealers in New York, has said: 
As an example of increased returns to the shippers from careful handling, I call attention to the 
fact that certain shipments of shad going to the New York market from North Carolina bring from 
25 to 40 per cent more than other shad from the same locality. * * * What I wish to impress upon 
the shippers and fishermen is that for every dollar invested in labor and ice in packing the fish they 
will receive ten dollars in return. 
Twenty more experiments were made with the same solution. Some of the ani- 
mals were decapitated and others were not, but the swim bladders and kidneys were 
removed from all. If the gills were thoroughly washed in the solution it was found 
that even fish with the head attached kept as well as those which were decapitated. 
Nevertheless, in fish treated with boric acid putrefaction first appears in the gills. A 
bushel of squeteague prepared in this way was put on the deck of the IT. S. Fish 
Commission schooner Grampus on the morning of August 12, 1898, and remained 
exposed to the sun throughout the day; the next morning, when cut up for bait, they 
showed no sign of decomposition. On another trip, 1,000 pounds of tile-fish were 
washed in the solution aud then packed in ice, where they remained for two weeks; 
when unpacked they were in a perfectly fresh condition. 
It is evident, then, that this solution retards the initial stages of putrefaction, 
even at the summer temperatures, and for a sufficient time for the fish to arrive at the 
market, where they may be iced and kept indefinitely. The solution of boric acid 
thus used is not a preservative , and it is not intended as such, but, like soap, it is an 
agent of cleanliness. As the fish are simply sponged over, the amount of the fluid that 
remains on a single fish is inconsiderable, and careful analysis fails to show more than 
the least trace in the flesh. Moreover, Chittenden and Gies have shown that boric 
acid given iu doses, even up to 3 grams per day, has no effect upon proteid metabolism 
or on the nutrition of the body; that it is not cumulative, but is quickly eliminated 
from the system, aud that it produces no renal complications. Its employment, 
therefore, as above recommended can have no injurious effect on the consumer. 
Iu preventing the growth of the micro-organisms which cause putrefaction we 
also eliminate the cause of ptomaine formation. Though some of the ptomaines are 
exceedingly poisonous, this is not characteristic of all, and it can be safely stated that 
the greater number of those that have been isolated are of a nonpoisonous nature. 
The kind of ptomaine formed depends on the kind of micro-organism which produces 
it, the character of the material acted upon, and the circumstances in which putrefac- 
tion takes place. As the ptomaines are only transition products, representing mere 
temporary stages in the great process of decomposition by which the complex organic 
molecule is transformed into the simple' inorganic state, it is evident that the kind of 
ptomaine present in putrid fish depends on the stage of putrefaction. Ptomaines 
formed when putrefaction takes place in free atmosphere will differ from those resulting 
from putrefaction where atmosphere is excluded. Almost any illness caused from 
infected food is spoken of as being due to “ptomaine poisoning,” but in the majority 
