  In this work we suggest a simplified interpretation of
Susskind-Horowitz-Polchinski correspondence between Schwarzschild black hole
and strings. Firstly, similarly to naive, classical mechanical Laplace
determination of the Schwarzschild radius, we suggest a simple, classical
mechanical equation. It determines amplitude of such sufficiently strong
classical elastic force that forbids escape of a Planck mass particle moving by
speed of light from end of corresponding classical elastic spring, simply
called dark spring. Also, by use of a formal identity between given elastic
force and Schwarzschild gravitational "force", we introduce phenomenologically
a simple quantization rule. It states that circumference (corresponding to
elastic force amplitude equivalent formally to Schwarzschild radius) holds
natural number of corresponding reduced Compton's wave length. (It is deeply
analogous to Bohr's quantization postulate in Bohr's atomic theory interpreted
by de Broglie relation.) Then, very simply (by simple algebraic equations only)
and surprisingly, we obtain such dark spring characteristics corresponding to
basic thermodynamical characteristics (Bekenstein-Hawking entropy and Hawking
temperature) for corresponding Schwarzschild black hole. Finally, simple
comparison between obtained dark spring characteristics and
Susskind-Horowitz-Polchinski correspondence, a simple correspondence between
strings and dark spring, i.e. classical linear harmonic oscillator follows.
Square root of the elasticity coefficient of the dark spring corresponds to
quotient of one string coupling g and Newtonian gravitational constant, or,
classical elasticity coefficient of the dark spring corresponds to reciprocal
(inverse) value of the square root of a string state excitation level N.
