52 BULLETIN 150, U. S. DEPARTMENT OF AGRICULTURE. 
the elimination of all costs of collecting. With these disappear like- 
wise the worry incident to the numerous elements of uncertainty 
involved in collecting. Thus at once are eliminated tugs and scows 
and their crews. The expense of collecting is but a trifle more than 
that of disposal by dumping through the cannery floor, and is de- 
cidedly cheaper than the method resorted to by some canneries. 
As the producer and consumer of the raw materials are one and 
the same, the conflict between the interests of the two disappears. 
Contracts working a hardship upon the one or the other are an ob- 
jectionable feature of the central rendering station plan as actually 
practiced. 
TTith a strictly by-products plant, overhead charges disappear. 
The cannery already has its clerical force and its sales and purchas- 
ing departments, which, without any increase in their force, are quite 
able to handle the slight additional labor incident to the by-products 
plant. Likewise it has the assistance of experienced foremen and 
mechanicians regularly attached to the cannery force, and the use of 
the supplementary equipment, such as machine shops, of the can- 
nery. Likewise, the docks, and frequently the unused floor space of 
the cannery, can^serve to cut down the initial expenditures. 
OTHER ADVANTAGES. 
The advantages other than monetary to accrue from the preserva- 
tion of the canneiw waste perhaps equal the financial advantages. 
The mam item gained, of course, is the greatly enhanced sanitary 
condition of the canneiy and its environs. To discuss here the moral 
effect of the most economical utilization of the fish now given to 
the packers " for the taking " on the residents of the State with which 
the packers come into important contact, perhaps, is too far afield 
for the purposes of this bulletin. The suggestion of such an advan- 
tage is made for what it is worth. 
THE PRODUCTION OF A MIXED FERTILIZER FROM FISH SCRAP 
AND KELP. 
KELPS. 
Since the shortness of the season during which the proposed cen- 
tral rendering station would be in operation has been suggested as 
a great obstacle in the way of the commercial success of that project, 
it becomes highly desirable to find some other use to which the 
equipment of the plant could be applied during seasons when no 
cannery waste would be available for rendering. All along the 
Pacific coast from Mexico to Bering Sea there is a vast quantity 
of fertilizer materials, the giant kelps, whose values are recoverable 
by a process similar in part to that prescribed for the conversion of 
