446 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1941 



Algin has been found to be equal to, or better than, the foreign gums 

 in most of the industrial applications that require the use of gums. 

 The usage of gums is more widespread than is generally known. 



Algin products are employed in the treatment of boiler water and 

 other industrial waters, in can-sealing compounds, in oil-well drill- 

 ing muds to seal off porous formations and resist the flocculating 

 action of brines, and as a medium for separating battery plates in 

 the manufacture of batteries. 



For resolving and preventing the incrustations of boilers, sodium 

 alginate is recognized by experts as one of the best preparations, as 

 it precipitates the lime salts in a state in which they can be readily 

 blown off. The charcoal formed during the manufacture of iodine 

 by the wet process, when combined with algin, has been largely used 

 for covering boilers under the name of carbon cement. Three per- 

 cent of algin is sufficient to make the carbon adhere, and a cool, light, 

 and adequate covering is formed. Agar is used as a suspending agent 

 in a wire-drawing lubricant. 



Just recently, a patent was given for the use of shredded agar to 

 retard evaporation in tobacco. 



Sharp found that agar activates nicotine in insecticide sprays to 

 a noteworthy degree. 



Certain species of seaweeds are used in different parts of the world 

 for making ornaments and curios. Species of Laminaria having a 

 hollow stipe are used for knife handles, since these kelps dry to a 

 very hard, hornlike substance. They are called artificial staghorn. 



THE PRESENT STATUS OF THE SEAWEED INDUSTRIES 



In the summer of 1941, as this paper is being written, it is difficult 

 to obtain recent figures from Europe and Asia regarding exports 

 and imports of seaweed material. The few figures given below, 

 however, give a slight indication of the importance of seaweed as 

 an article of commerce. 



AGAR 



Japan has long been the world's leading producer of agar and is 

 the only country that exports this product to any great extent. Only 

 small quantities of an inferior grade of agar are reported to have 

 been produced in China and the Soviet "Union. In 1938 the Nether- 

 lands Indies developed a small industry supplemented by a second 

 establishment opened by a well-known ice-manufacturing concern. 

 The seaweed needed by these concerns is obtained along the Java 

 and Celebes coasts, whence comes much of the seaweed used, in the 

 Japanese manufacture of agar. The seaweed could be purchased 

 from the natives for as little as $1.65 per picul of 136 pounds. Suffi- 



