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High and low resolution $IUE$ spectra of V838 Her in the early outburststages exhibit a strong absorption feature shortward of $\lambda$3130. Wediscuss the nature of this spectral feature and provide convincing evidencethat it corresponds to the blue-shifted resonance doublet of singly-ionized$^7$Be, recently discovered in other novae. During the evolution of theoutburst the appearance of an emission feature close to $\lambda$3130 is alsoidentified as $^7$Be II $\lambda$3132 because the usual identification as the OIII $\lambda$3133.7 Bowen fluorescence line is hardly compatible with both theknown oxygen under-abundance in the nova ejecta and the low optical depths inthe nebula due to the high outflow velocity. The average $^7$Be abundancerelative to hydrogen, estimated by four different methods, i.e. the $^7$Be II /Mg II absorption ratio, and the $^7$Be II / Mg II, $^7$Be II / He II$_{1640}$,and $^7$Be II / H$\beta$ emission ratios is N(Be)/N(H) $\approx$ 2.5 $\times10^{-5}$ (by number), i.e. $\approx$ 1.7 $\times 10^{-4}$ by mass. Thiscorresponds to an overproduction of $^7$Be by about 1 dex in comparison withthe theoretical models of massive CO and ONe novae. Since $^7$Be all convertsinto $^7$Li, the $^7$Be/H abundance implies a $^7$Li/H overabundance of about 4dex over the $^7$/H meteoritic value and indicates a total ejected mass of$^7$Li of $\approx$ 9.5$\times$10$^{-10}$ $M_{\odot}$. These data are in linewith previous observations and indicate that large amounts of $^7$Li can besynthesized in a variety of novae, including very fast ONe novae.

Absorption and emission features of $^7$Be{\sc II} in the outburst spectra of V838 Her (Nova Her 1991)