304 ANXU.UL. BEPORTS Ui' DEPARTMENT OF AGiUCULTURE. 



Toward the end of the year efforts were made to put iodine on a 

 prothiction basis. Ap])aratiis has been constructed and put in opera- 

 tion. ^Methods of production are being rapidly improved and stand- 

 ardized. A substantial revenue is expected from the sale of iodine 

 during the coming year. Cooperative researches on the distillation 

 pi-oducts from kelp have been arranged for in several laboratories. 

 Dr. A. S. Wheeler, professor of organic chemistry of the University 

 of North Carolina, is making a study of the neutral oils obtained 

 from kelp tar. Dr. Fred H. Ehodes, of the Barrett Co., is investigat- 

 ing the kelp-tar acids or phenolic bodies. Dr. L. H. Duschak, of the 

 Bureau of Mines, has made tests with crude kelp oils, redistilled oils, 

 and kelp acids as flotation agents in the concentration of a variety 

 of ores. The results have shown the oils to possess high potential 

 value as flotation agents. Their commercial practicability will depend 

 on the cheapness and uniformit}^ with which they can be manufac- 

 tured. The production of ammonia remains undeveloped, although 

 problems in connection therewith have been studied throughout the 

 year. 



The study of forms of retorts for the destructive distillation of 

 kelp continued throughout the year with a view to the construction 

 of such retorts immediately on the beginning of the new year. Mate- 

 rials for this construction have been purchased, and that w^ork will 

 be pushed to the earliest possible completion. Slot retorts will be 

 built and a full equipment of tar condensers, gas scrubbers, and am- 

 monia liquor recovery apparatus will be installed. It is not expected 

 by this installation entirely to solve the problems involved in the 

 utilization of distillation products, but it is believed that we have 

 gone far enough now to enable us to build retorts which will handle 

 the plant's output of dry kelp in a convenient and economical man- 

 ner. We are anxious to see this installation completed, among other 

 reasons, on account of the final solution of the dust and smoke prob- 

 lems which it will undoubtedly represent. The completion of the 

 electric furnace and of the dry kelp retorts represent the two big 

 problems to be rushed to completion. The}'- should represent econo- 

 mies in both materials and labor. 



Complete cost data in the various processes have been kept. Curves 

 representing the various operations have been plotted which show in 

 each instance material progress toward more efficient operation. It 

 has been necessary to reduce the operating force, but this has been 

 done without the necessity of suspending any operations. 



Plans for the new year contemplate the development of the output 

 of bleaching carbon to not less than 1,500 pounds per day. This will 

 be followed by the construction of new retorts for the destructive 

 distillation of dry kelp, and, as our understanding makes it possible, 

 the installation of apparatus for the proper and most advantageous 

 treatment of the distillation products, namely, ammonia, neutral 

 oils of various gravities, tars, acids and phenolic compounds, pitch, 

 and combustible gas. Most of the supplies for this installation like- 

 wise have been purchased. 



In order to save the last of the potash which remains in the char 

 as it emerges from the lixi viator, a third vacuum filter of the type 

 already installed is being put in place, which will make the lixivia- 

 tor three stages, countercurrent, instead of two stages, as at present. 



