Convert from tahil [China] to fother [lead]

Unit Definition (tahil [China])
The tahil is a traditional unit of weight used throughout eastern Asia. During the colonial period, the tahil was more or less standardized throughout the region at 4/3 ounce avoirdupois (1/16 catty, 1/12 pound, or about 37.8 grams). In Japan, however, the tahil was identified with a slightly smaller traditional unit and is considered equal to 1.323 ounces (37.51 grams). The tahil is usually considered equal to the Chinese liang.

Unit Definition (fother [lead])
The fother is a traditional English unit of weight for lead. The fother, equal to 30 fotmals, was always a little smaller than a (long) ton. The original version seems to have been equivalent to 2160 avoirdupois pounds, and the version still being used in the nineteenth century was equal to 19.5 hundredweight or 2184 pounds.