  We have carried out dual-comb spectroscopy and observed in a simultaneous
acquisition a 140-THz-wide spectrum from 1.0 to 1.9 {\mu}m using two
fiber-based frequency combs phase-locked to each other. This ultra-broad
wavelength bandwidth is realized by setting the difference between the
repetition rates of the two combs to 7.6 Hz using the sub-Hz-linewidth fiber
combs. The recorded spectrum contains five vibration-rotation bands of
C${_2}$H${_2}$, CH${_4}$, and H${_2}$O at different wavelengths across the
whole spectrum. The determined transition frequencies of C${_2}$H${_2}$ agree
with those from the previous sub-Doppler resolution measurement of individual
lines using CW lasers within 2 MHz.
