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We aim to understand the accretion history of the Milky Way by exploring thevertical and radial properties of the Galactic thick disc.  We study the chemical and kinematic properties of roughly a thousand spectraof faint magnitude foreground Galactic stars observed serendipitously duringextra-galactic surveys in four lines-of-sight: three in the southern Galactichemisphere (surveys of the Carina, Fornax and Sculptor dwarf spheroidalgalaxies) and one in the northern Galactic hemisphere (a survey of the Sextansdwarf spheroidal galaxy). The foreground stars span distances up to 3kpc fromthe Galactic plane and Galactocentric radii up to 11kpc.  Only three lines-of-sight have a sufficient number of foreground stars for arobust analysis. Towards Sextans in the Northern Galactic hemisphere andSculptor in the South, we measure a consistent decrease in mean metallicitywith height from the Galactic plane, suggesting a chemically symmetric thickdisc. This decrease can either be due to an intrinsic thick disc metallicitygradient, or simply due to a change in the thin disc/thick disc populationratio and no intrinsic metallicity gradients for the thick disc. We favour thelatter explanation. In contrast, we find evidence of an unpredicted metal-poorpopulation in the direction of Carina. This population was earlier detected byWyse et al. (2006), but our more detailed analysis provides robust estimates ofits location (|Z|<1kpc), metallicity (-2<[M/H]<-1 dex) and azimuthal orbitalvelocity (V_phi ~120 km/s).  Given the chemo-dynamical properties of the over-density towards the Carinaline-of-sight, we suggest that it represents the metal-poor tail of thecanonical thick disc. In spite of the small number of stars available, wesuggest that this metal-weak thick disc follows the often suggested thick discvelocity-metallicity correlation of dV_phi/d[M/H]~40-50km/s/dex.

Through thick and thin: Structure of the Galactic thick disc from extragalactic surveys