While these eight institutions are primarily engaged in commercial banking, they are also promoters on a large scale of German industry and commerce, both at home and abroad. Through interlocking directorates, stock ownership, and in other ways, they are closely allied with the leading industrial and transportation interests of the Empire, and they have been and are leaders in the promotion of these interests in other parts of the world, notably in the Orient, South America, and Africa. They are, therefore, leaders on the stock as well as the discount markets of the country, and are widely influential in investment as well as commercial banking affairs. These, as well as the other commercial banks, consisting for the most part of local institutions and those catering to special interests, use the Imperial Bank for rediscounts, for transfers of funds between different parts of the country, and as a depository for surplus funds. They do not normally keep on hand more cash than is needed for till purposes. Being in easy reach of an office of the Imperial Bank, supplies can be obtained at any time by checks drawn against credit balances or through rediscounts of commercial bills. Special accounts are carried for transfer purposes and are used even in the transfer of funds between different offices of the same institution. On account of its right to issue notes against commercial securities, the Imperial Bank has the power to meet the demands made upon it and to supply the country with an elastic medium of exchange. The levy of a tax upon the excess of the issues above a prescribed maximum prevents perfect elasticity, unless this maximum be kept above the highest point which the circulation would normally reach, since the actual levy of the tax forces the rate of discount to such a point as to seriously restrict commercial operations. However, since the line between commercial and investment banking is not drawn by the great Berlin banks with the care that is desirable, and since they have been able at times, especially on account of their foreign connections, to embarrass the Imperial Bank in its efforts to maintain adequate specie reserves, such a tax is probably a desirable safeguard against over-expansion of credit. _5. The Canadian System_