Pouring solutions of chemicals in the bottle, Amateurs are plastic or glass funnels. First trouble do not deliver: special ribs on the outer surface do not allow them to fit snugly to the necks, and displaced fluid with the air out of the bottles without interference. Edge for glass can be formed by bending, as shown in the figure, the cut copper wire Ø 1 mm.
A. KAMALOV, Obninsk, Kaluga region
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