  We re-investigated the `spectro-temporal' behaviour of the source XTE
J1859+226 in X-rays during its outburst phase in 1999, by analysing the RXTE
PCA/HEXTE data in 2 - 150 keV spectral band. Detailed analysis shows that
although the evolution pattern of the outburst followed the typical q-shaped
profile, an absence of `canonical' soft state and a weak presence of
`secondary' emission are observed. The broad-band spectra, modeled with high
energy cutoff, shows that the fold-energy increases monotonically in the hard
and hard-intermediate states followed by a random variation in the
soft-intermediate state. We attempted to estimate the mass of the source based
on the evolution of Quasi-Periodic Oscillation (QPO) frequencies during rising
phase modeled with the propagating oscillatory shock solution, and from the
correlation of photon index and QPO frequency. It is also observed that during
multiple ejections (observed as radio flares) the QPO frequencies are not
present in the power spectra which is followed by softening of the spectra
(disk flux increases or high energy flux decreases). These results are the
`possible' indication that the Comptonized corona, which could be responsible
for the generation of QPO and for the non-thermal Comptonized component of the
spectrum, is disrupted and the matter gets evacuated in the form of jet. We
attempted to explain the complex behaviour of the source during the entire
outburst and the nature of the disk-jet connection in the context of two
different types of accreting flow material, in presence of magnetic field.
