Recent research has considered a wider range of 19th century sources than had been possible by 20th-century writers. The evidence from these sources suggests that even in the mid-1830s the genre was still developing, which shifts the period of the rise and flourishing of shanties to a bit later than was previously accepted. The general silence of the historical record on modern shanties until as late as the 1840s, even as shipping shifted to the even faster clipper ships, suggests that they may not have come into widespread use until the middle of the century. They received a boost from the heavy emigrant movement of gold rushes in California and Australia. Popular shanties of the 1850s included "A Hundred Years Ago", "One More Day", "Santiana", "Haul on the Bowline", "Across the Western Ocean", and especially "Stormalong".