﻿30 BULLETIN 2, U. S. DEPARTMENT OF AGRICULTURE. 



As was stated, the wet scrap is dropped directly into the white-hot 

 gases from the furnace. The scrap as it enters is in the form of 

 lumps varying in size from the smallest particles to masses several 

 inches in diameter. With a heat intense enough to dry the larger 

 lumps in a maximum of 20 minutes, it is evident that the finest par- 

 ticles must be utterly consumed. The greater speed with which they 

 travel must save much of that in the form of the less fine particles. 

 This is an a priori conclusion, but is practically indisputable. 

 "Whether the loss is serious or not can not be said until more experi- 

 mental evidence is adduced. 



When there is much combustion of the fish the fact is further 

 attested by the odor of the smoke which emerges from the " stack " 

 of the drier. This is then a heavy smoke, largely mixed with steam 

 and distillation products and smelling most offensively of scorched 

 flesh. It carries also numerous fine particles of scrap, which in the 

 course of a year's run must represent a considerable loss. 



In certain neighborhoods where the majority of the residents are 

 not in sympathy with the industry the hot-air driers are not used 

 at all, or if used, are operated only at night or when the wind is 

 offshore. A tall stack, while an expensive adjunct to a plant, to a 

 considerable extent would alleviate this objection to the use of the 

 drier. 



GRINDING AND BAGGING. 



After drying it remains only to bag and ship the fish scrap. Some 

 scrap is shipped in bulk, being transferred by conveyer directly to 

 the hold of the transporting vessel. Much is bagged without further 

 treatment ; some is ground to a meal before bagging. For the ground 

 scrap' a slightly higher price is obtained, representing little more than 

 the cost of grinding. In certain mills the scrap is mixed (" manipu- 

 lated ") with phosphate and potash carriers to produce a so-called 

 complete fertilizer, and is thus marketed under brand names. Other 

 companies are planning an extension of their present operations in 

 that direction. In certain other instances the scrap is shipped to 

 manipulating plants owned and operated by the fish-scrap company. 

 In all other cases, with the exception of the small amounts used 

 locally and as chicken feed, the scrap is shipped directly to the 

 mixers of finished fertilizers. 



THE FACTORY. 



In locating a factory for the manufacture of fish scrap an attempt 

 is made to obtain a combination of deep water, protected harbor, 

 and nearness to fishing grounds. (PI. VI.) An effort is made fur- 

 ther to find a location that is sufficiently isolated to obviate the 

 danger of litigation on the grounds of being a nuisance because of 



