Finely cut up some leaves and fill a mortar to about 2 cm depth. Add a pinch of sand and about six drops of propanone from the teat pipette. Grind the mixture with a pestle for at least three minutes. On a strip of chromatography paper, draw a pencil line 3 cm from the bottom. Use a fine glass tube to put liquid from the leaf extract onto the centre of the line. Keep the spot as small as possible. Allow the spot to dry, then add another spot on top. Add five more drops of solution, letting each one dry before putting on the next. The idea is to build up a very concentrated small spot on the paper. Attach the paper to the pencil using sellotape so that when placed in the beaker, the paper is just clear of its base. Place no more than about 10 cm3 of propanone in the beaker and hang the paper so it dips in the propanone. Ensure the propanone level is below the spot.