A distinction is usually made between ezxporl industries and home industries, the latter catering mainly for the domestic market. The export industries include some of the oldest industries in the country, e.g., mining and wood manufactures. Since 1623 mining has constituted an important factor in Norwegian foreign trade. In the last thirty years a new export industry, the electro-chemical and electro-metallurgical, has ‘grown to big dimensions. This is due, in the first place, to the fact that the great volume of cheap hydro-electric power affords excep- tionally favourable conditions for such an indus- try. The value of the output of electro-chemical and electro-metallurgical products in 1932 exceed- ed 140 million Kroner. The largest output under this head stands to the account of the Norsk Hydro company, who in that year turned out about 300,000 tons of nitrate of lime and «Norwegian nitrate of lime» alone. Another large and particularly important export industry is food canning. The value of this produc- tion was more than 40 million Kroner in 1932. According to official returns the value of export manufactures in 1932 was 442 million Kroner. The total value of Norwegian export trade in the same year was 561 million Kroner. Home industries, too, have reached a high stage of development and have greatly assisted in rendering Norway independent of foreign markets. These manufactures mainly comprise articles of 81