1957. Other modes of covering. Various modes of covering have been invented, but most of them after a short trial have been found of little value. Among the best, however, may be mentioned what is called transparent sheeting, which consists of calico washed over with a preparation of wax. Whitney's patent composition for preparing calico and even muslin for frames was much praised about the time of its invention is 1843, but it is now seldom heard of.