This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
The heated tallow or wax of a candle runs down the sides and this results in a considerable waste. This waste can be stopped by coating the new candles with white varnish and laying them aside for a few days to harden. The varnish will keep the melted tallow or wax from running away and it is used in the wick.