Convert from libra [ancient Rome] to chalder, chaldron

Unit Definition (libra [ancient Rome])
The libra [ancient Rome] is a traditional unit of weight. The libra was the Roman unit from which the English pound is descended; the symbol "lb" for the pound comes from this unit. The Roman libra contained only 12 unciae (ounces) and was about 0.722 English pound. The word "libra" is sometimes used now for the kilogram, a much larger unit.

Unit Definition (chalder, chaldron)
The chalder, chaldron is a traditional British unit of volume or weight used for dry commodities such as coal or lime. As a volume measure, the chaldron is equal to 36 bushels, or 288 British Imperial gallons; this is equivalent to 46.237 cubic feet or 1.3091 cubic meters. As a measure for coal, the chalder equals 1/8 keel or 53 hundredweight (5936 pounds or 2692.52 kilograms). The words "chalder," "chaldron," and "cauldron" are English spellings of the same old French word, which originally meant a large kettle.