The schooner barge was the final development of the working sailing ship. The design originally evolved in the 1870s on the Great Lakes, where it was found that sailing ships could be more profitably towed from place to place than sailed. No longer subject to the vagaries of the wind, such trips could be made on a scheduled basis, and with reduced labor costs. The idea spread into general use, resulting in the conversion of many sailing ships into barges. Ironically, most of the vessels that were converted to schooner barges were not actually schooners, but square-rigged ships. Square-riggers, with their large and expensive crews of skilled sailors, became uneconomical to operate in the face of ever-improving steam power, while more efficient schooners managed to compete for a few years longer.
Artifacts recovered after long immersion in salt or freshwater require conservation treatment if they are to last. On exposure to high concentrations of oxygen in the air, iron artifacts will bloom into piles of rust. Wood will crack and split if dried out improperly. Organic materials will crumble to dust.
The manual below details conservation methods for many types of materials and artifacts.