The Austin brothers soon incurred debts, causing the collapse of the company. After the Virginia lead business failed, Moses skipped out to avoid imprisonment and the consequences of debt, which was then customary for debtors in the U.S. under traditional English law (now being developed for U.S. federal and state codes), and looked toward the rich lead deposits in Missouri, then a part of upper Spanish Louisiana. In December 1797, Austin and a companion traveled to investigate the Spanish mines. In 1798, the Spanish colonial government granted to Moses one league (4,428 acres). In return he swore allegiance to the Spanish Crown and stated he would settle some families in Missouri. Stephen remained behind to salvage the Virginia business, creating a rift between the two brothers that would last for much of the rest of their lives. The state of Virginia seized much of the property Moses owned and broke up the various operations, which were later purchased from the state at great discounts by Thomas Jackson and his partners — they would later build the Jackson Ferry Shot Tower, one of the few extant shot towers in United States, at this location.