This substance, variously known as cachuchu, caoutchouc, gum elastic, and India-rubber, was first introduced into Europe in 1730, where it was regarded merely as a curiosity, useful for erasing pencil marks, but valueless for any practical use. Ships from South America brought it over as ballast, but it was not until ninety years after its first appearance in Europe that any effort was made to utilize it. About the year 1820 it began to be used in France in the manufacture of suspenders and garters, India-rubber threads being mixed with the materials used in weaving those articles. It was also used in blacking and varnish, and some years later, Mackintosh brought it into prominent notice by using it in his famous water-proof coats, which were made by spreading a layer of the gum between two pieces of cloth. The gum was thus protected from the air, and preserved from injury. Up to this time, it was almost an unknown article in the United States, but in 1820 a pair of India-rubber shoes were exhibited in Boston. Even then they were regarded as merely a curiosity, and were covered with gilt foil to hide their natural ugliness. In 1823, a merchant, engaged in the South American trade, imported five hundred pairs from the Para district. He had no difficulty in disposing of them; and so great was the favor with which they were received, that in a few years the annual importation of India-rubber shoes amounted to five hundred thousand pairs. It had become a matter of fashion to wear these shoes, and no person's toilet was complete in wet weather unless the feet were incased in them; yet they were terribly rough and clumsy. They had scarcely any shape to them, and were not to be depended on in winter or summer. In the cold season they froze so hard that they could be used only after being thawed by the fire, and in summer they could be preserved only by keeping them on ice; and if, during the thawing process, they were placed too near the fire, there was danger that they would melt into a shapeless and useless mass. They cost from three to five dollars per pair, which was very high for an article so perishable in its nature.