Polystyrene mounting medium.

Polystyrene mounting medium obtainable Ltd, 20 Du The medium described by Kirkpatrick One pounc and Lendrum (1939) and named by them mountant DPX (Distrene plasticised in xylene) was (75°% one replaced by a better formula in 1941. This medium BPS (butyl phthalate plasticised styrene) has given excellent and economical service until recently. The current trouble was not due to the makers of the polystyrene. Natural Styron 686E (natural signifies clear!), made by Messrs Dow Chemical Ltd, is now marketed in the smaller quantities in Britain as Polystyrene SA99/W Crystal by Messrs R. H. Cole References Ltd, 85 Southdown Road, Harpenden, Kirkpatrick Herts. Laboratories preparing their own Mountinl BPS are advised to use this formula: preparati Dissolve 12 g of the crystals in a mixture colour. Jo of 40 ml xylene and 4 ml dibutyl phthalate ology, 49, (Lendrum et al., 1962 and 1972). This can Kirkpatrick be stored in glass or conveniently for use Further in screw-capped metal tubes filled from synthetic ,the open bottom end which is then closed balsam; by folding over with pliers. These 'CollapJournal o) sible Tubes, 1 inch by 5i inches' are 441-443. from Messrs Adelphi (Tubes) incan Terrace, London N18BZ. d (0 45 kg) of crystals provides for more than 6000 coverslips inch square).