BUREAU OP SOILS. 225 



tons of actual potash annually. Slight modifications of operating 

 practice would increase this total to at least 100,000 tons. A bulletin 

 giving the results of this work is now in press. 



A similar survey of the blast-furnace industry was begun and is 

 now in progress. In this work the Bureau of Mines is cooperating 

 to the extent of assisting in the collection of samples. 



The appropriation for an experimental kelp plant became avail- 

 able in August, 191(), and shortly thereafter work was actively begun. 

 Difficulty was found in securing deliveries of the necessary materials 

 and machinery, but by the end of the fiscal year the plant was prac- 

 tically completed and ready for operation. 



The plant as it stands includes a 115-ton self-propelled harvester; 

 wharf with GOO-foot conveyor; derrick with grab bucket for unload- 

 ing kelp from the harvester; a transformer house containing electric 

 operating equipment ; chopper and receiving bin ; storage bins of 300 

 tons capacity; drier house containing three 50-foot rotar}?- driers with 

 dust chambers, blowers, conveyors, and motors; four 25-foot retorts 

 for distilling the dried kelp, with storage bin above and discharging 

 apparatus; gas line from retorts with burners, valves, tar, and dis- 

 tillate seal and receiving vat ; four air lines from blowers to furnaces; 

 a millhouse with storage bins for char with conveyors and grinding, 

 sacking, and leaching apparatus, and vat for brine ; a machine shop 

 and equipment; an office building; and a 10,000-barrel storage tank 

 for fuel oil, with pipe lines to driers. 



Under construction is an evaporator house to contain evaporator, 

 crystallizer, salt traps, preheater, vacuum pump, condenser, receiving 

 vats, storage bins, vapor and brine lines, and boiler. This equipment 

 has all been contracted for and some of it delivered. 



Much of the equijoment entering into the plant has been secured 

 second hand at a substantial reduction over current prices for new 

 material, and economy in construction has been practiced wherever 

 it was possible without sacrificing efficiency. In this way it has 

 been possible to construct the plant for less than $100,000 instead of 

 the original estimate of $150,000, despite the high cost of labor and 

 materials. Of the original appropriation of $175,000 there remains 

 sufficient for operating expenses during the current fiscal year, unless 

 unforeseen expenditures should become necessary. Active operations 

 will begin in a few weeks, as soon as the new kelp growth is available. 



In connection with the erection of the plant, studies of the life 

 history of the kelp have been made and much information having 

 a direct bearing on the use of kelp commercially has been secured. ' 

 It seems likely that there is an annual dying of the kelp in southern 

 California waters, followed by an immediate new growth. Certainly 

 this year there has been extensive dying back of the kelp, and many 

 of the heavier beds have disappeared temporarily. These are, how- 

 ever, now recovering rapidly through new growth, and operations 

 will not be long retarded from this cause. 



During the year the bureau has received a large number of sam- 

 ples of supposed fertilizer materials for analysis, and a large body of 

 correspondence on fertilizer matters has also been handled. Both 

 these activities have been materially increased by the general interest 

 in fertilizers, owing to the prevailing high prices, the short supply 

 of many important ingredients, and the unusually heavy demand. 



33382"— AGR 1917 15 



