  The black hole system 1E${\thinspace}$1740.7$-$2942 is usually the brightest
hard X-ray source (above 20 keV) near the Galactic Center, but presents some
epochs of low emission (below the INTEGRAL detection limit, for example). In
this work, we present the results of studies on 1E${\thinspace}$1740.7$-$2942
over 10 years, using the instruments ISGRI/IBIS and JEM-X, both on board the
INTEGRAL observatory. We fit the spectra with both the compTT and cutoffpl
models. According to the fits and taking the mean value over the 10 years, we
have obtained a plasma temperature in the range $\sim$20$\,-\,$90$\thinspace$
keV, and an average powerlaw index of 1.41 ($\sigma$=0.25). We have also made a
Lomb$\,-\,$Scargle periodogram of the flux in the 50$\,-\,$20${\thinspace}$keV
band and found two tentative periods at 2.90 and 3.99${\thinspace}$days. We
present here the preliminary results of this ongoing work.
