  High resolution spectra of Comet 8P/Tuttle were obtained in the frequency
range 3440.6-3462.6 cm-1 on 3 January 2008 UT using CGS4 with echelle grating
on UKIRT. In addition to recording strong solar pumped fluorescent (SPF) lines
of H2O, the long integration time (152 miutes on target) enabled eight weaker
H2O features to be assigned, most of which had not previously been identified
in cometary spectra. These transitions, which are from higher energy upper
states, are similar in character to the so-called 'SH' lines recorded in the
post Deep Impact spectrum of comet Tempel 1 (Barber et al., 2007). We have
identified certain characteristics that these lines have in common, and which
in addition to helping to define this new class of cometary line, give some
clues to the physical processes involved in their production. Finally, we
derive an H2O rotational temperature of 62+/- K and a water production rate of
(1.4+/-0.3)E28 molecules/s.
