Calcium Hypophosphite: Phosphorus Boiled with Milk of Lime, Procter

Calcium hypophosphite is the salt from which sodium hypophosphite, the reducer in electroless nickel, is made. Procter's formula (US Dispensatory, 1907): boil phosphorus with milk of lime until no more gas comes off, filter, and evaporate. The gas is phosphine: deadly, and it bursts into flame by itself in air. Outdoors only, never alone. Our batch is Procter's divided by 8. The picture: our own drawing.