Abstract: A peripheral pump for feeding fuel from a supply tank to the internal combustion engine of a motor vehicle, in which, in a pump chamber (17) embodied by at least two adjacent walls (18, 19), a revolving circular-cylindrical impeller (12) is disposed, on whose face end in an intake-side wall (18) and an outlet-side wall (19) of a medium a feed conduit (41, 42) is provided, which communicate with one another at an angle (.beta.) via a radially disposed connecting conduit (49, 51) in the wall (18, 19) having a pressure region (34, 35) cooperating with the impeller (12), and these pressure regions (34, 35) can be acted upon by the pressure building up increasingly in the feed conduit (41, 42), thus bringing about an equalization of axial force with respect to the impeller (12) at the walls (18, 19) of the pump chamber (17).

Abstract: A photometric absorption detector, in particular for the use in liquid chromatography is provided, in which a test cell is penetrated by the rays emitted by a light source and in which the absorption of certain wave length ranges of the light by the sample is recorded by means of a photodetector arrangement. Means for the spectroscopical dispersion of the light emerging from the test cell are provided, and the photodetector arrangement can be displaced within the spectrum. There may be two independently displaceable photodetectors, one of which may be set to a measuring wave length, while the other one may be set to a reference wave length.