1762 LAWS OF MARYLAND [CH. 761

agreement with the National Capital Park and Planning
Commission, for any other land held or acquired by the
United States, the State of Maryland or any other public
body or agency and deemed by the Commission, in its sole
discretion, as more suitable for playground and recreation
purposes than the land held by it and so offered in
exchange. Any such exchange may be accompanied by a
partial cash consideration moving either to or from said
Commission and any such exchange, effected as aforesaid,
shall be deemed and is hereby declared to be an acquisi-
tion of land for the public uses hereinabove defined.

For the purpose of paying principal and interest on the
bonds of Series L issued by the Commission as of January
1, 1950, to which the full faith and credit of said Com-
mission and of Montgomery County are irrevocably
pledged, the County is hereby directed annually to levy
upon all assessable property within the limits of that
portion of the Maryland-Washington Metropolitan Dis-
trict within Montgomery County, an ad valorem tax in
rate and amount sufficient to meet the annual debt service
requirements on said bonds so long as any of such bonds
shall remain outstanding and unpaid, and at the same inter-
vals hereinabove provided for remittance by the County to
the Commission of the proceeds of said 7c tax, the County
shall likewise remit to the Commission the proceeds of
the tax which it is herein directed to levy to meet debt
service on said bonds; provided, however, that the levy of
said tax shall no longer be mandatory hereunder when
and if the Commission shall have accumulated in a sinking
fund established for that purpose, an amount sufficient to
pay the principal of all of said bonds when and as the
same shall become due or shall be tendered for prior
redemption, but thereafter said tax shall be levied only
in an amount sufficient to pay the annual accruing inter-
est on such of said bonds as shall be outstanding and
unpaid in any tax year; but provided, further, nothing
herein contained shall relieve Montgomery County from
its unconditional obligation to pay the principal and inter-
est of any such bonds as and when the same respectively
become due, nor to levy ad valorem taxes upon all prop-
erty subject to assessment for taxation within the corpo-
rate limits of the entire County should any such tax
become necessary for such payment, irrespective of
whether the Commission shall have accumulated sufficient
funds for said purpose or not, it being the intent hereof
that Montgomery County shall remain liable for the pay-
ment of principal and interest of said bonds in the event
the Commission shall fail, for any reason, to make such