  We analyze 60 months of all sky data from the Fermi-LAT. The Fermi Bubble
structures discovered previously are clearly revealed by our analysis. With
more data and, consequently, better statistics we can now divide each bubble
into constant longitude slices to investigate their gross $\gamma$-ray spectral
morphology. While the detailed spectral behaviour of each slice derived within
our analysis is somewhat dependent on the assumed background model, we find,
robustly, a relative deficit of the flux at low energies (i.e., hardening)
towards the top of the South Bubble. In neither Bubble does the spectrum soften
with longitude. The morphology of the Fermi Bubbles is also revealed to be
energy dependent: at high energies they are more extended. We conclude from the
gamma-ray spectrum at high latitudes that a low energy break in the parent
cosmic ray population is required in both leptonic and hadronic models. We
briefly discuss possible leptonic and hadronic interpretation of this
phenomenology.
