national banking associations, each with an unimpaired capital and
surplus of not less than twenty per cent and an aggregate capital and
surplus of not less than $5,000,000, may form national currency
associations. These associations are to have power to render available,
for the basis of additional circulation, "any securities, including
commercial paper, held by a national banking association."
(2) To obtain this additional circulation, any bank belonging to a
national currency association having circulating notes outstanding
secured by United States bonds to an amount not less than forty per cent
of its capital stock, and having the required unimpaired capital and