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tokens: IRTF spectral library and the present spectrum of V1534 Sco, and to the Fitzpatrick ( 1999 ) reddening law. Figure 2. Upper panel: expanded view from Fig. 1 around the far-red Ca ii triplet and head of the Paschen series. Lower panel: a plot of the residuals after subtracting the M6III spectrum from that of V1534 Sco. The strongest emission lines are identified. 3.2 The emission-line spectrum There are several emission lines visible in the IRTF spectrum of V1534 Sco, as illustrated in the zoomed views of Figs 2 – 4 . Fig. 2 focuses on the 0.84−0.94 μm region. The O i 0.8446 μm emission line is already evident in the direct spectrum of V1534 Sco of the top panel. Other lines like the Ca ii triplet and hydrogen Paschen series become more clearly visible once the template M6III spectrum is subtracted from that of V1534 Sco, as illustrated in the bottom panel of Fig. 2 . We have explored the large number of ∼200 spectra of symbiotic stars surveyed in the spectral atlas of Munari and Zwitter ( 2002 ), and found that Hen 3-1410 provides the closest match with V1534 Sco. Their observed spectra are compared in Fig. 3 . The strength of O i 0.8446 μm and the simultaneous absence of O i 0.7772 μm are direct evidence that a strong Lyman-β fluorescence (Bowen 1947 ) is at work in Hen 3-1410. This could also be the case for V1534 Sco, but the low signal-to-noise ratio (S/N) at the blue end of its spectrum does not allow us to judge about the presence and intensity of O i 0.7772 μm. Figure 3. Comparing the blue end of the IRTF spectrum with that of the M6III symbiotic star Hen 3-1410 taken from the spectral atlas of symbiotic stars by Munari Zwitter ( 2002 ). The spectral region explored in more detail in Fig. 4 is that of He i 1.0830, Paschen-γ 1.0938, and O i 1.1287 μm which are clearly present in emission in the spectrum of V1534 Sco. They well match what is normally seen in symbiotic binaries, as proved by the comparison with T CrB in the bottom panel of Fig. 4 (this IRTF spectrum of T CrB – itself a NwSS – was taken on the same night and with the same instrumental set-up of V1534 Sco.). The only significant difference between T CrB and V1534 Sco is the deep P-Cyg absorption that the latter displays for He i 1.0830 μm. It is not an observational artefact and there is no photospheric line at this position that could mimic such a P-Cyg profile, as proved by the over-plotted spectrum for the M6III template. P-Cyg profiles are sometimes observed for He i lines in symbiotic stars (e.g. Smith 1981 ), their presence and intensity being usually a function of orbital phase (e.g. Munari 1993 ). Figure 4. Similar to Fig. 2 , the upper panel shows an expanded view from Fig. 1 , this time around the He i 1.0830 μm line, while the central panel presents the result of the subtraction of the M6III spectrum from that of V1534 Sco. Note the presence of a deep P-Cyg absorption component for the strong He i line. For comparison a spectrum of T CrB, an M3III symbiotic star