  Long-slit medium-resolution spectra of the Galactic globular clusters (GCs)
NGC6229 and NGC6779, obtained with the CARELEC spectrograph at the 1.93-m
telescope of the Haute-Provence observatory, have been used to determine the
age, helium abundance (Y), and metallicity [Fe/H] as well as the first estimate
of the abundances of C, N, O, Mg, Ca, Ti, and Cr for these objects. We solved
this task by comparing the observed spectra and the integrated synthetic
spectra, calculated with the use of the stellar atmosphere models with the
parameters preset for the stars from these clusters. The model mass estimates,
$T_{\rm eff}$, and log~g were derived by comparing the observed
"color-magnitude" diagrams and the theoretical isochrones. The summing-up of
the synthetic blanketed stellar spectra was conducted according to the Chabrier
mass function. To test the accuracy of the results, we estimated the chemical
abundances, [Fe/H], $\log~t$, and $Y$ for the NGC5904 and NGC6254 clusters,
which, according to the literature, are considered to be the closest analogues
of the two GCs of our study. Using the medium-resolution spectra from the
library of Schiavon et al., we obtained for these two clusters a satisfactory
agreement with the reported estimates for all the parameters within the errors.
We derived the following cluster parameters. NGC6229: [Fe/H]=-1.65 dex, t=12.6
Gyr, Y=0.26, [\alpha/Fe]=0.28 dex; NGC6779: [Fe/H]=-1.9 dex, t=12.6 Gyr,
Y=0.23, [\alpha/Fe]=0.08 dex; NGC5904: [Fe/H]=-1.6 dex, t=12.6 Gyr, Y=0.30,
[\alpha/Fe]=0.35 dex; NGC6254: [Fe/H]=-1.52 dex, t=11.2 Gyr, Y=0.30
[\alpha/Fe]=0.025 dex. The value [\alpha/Fe] denotes the average of the Ca and
Mg abundances.

Solar and Stellar Astrophysics