It may seem strange, then, that the literature on American bark canoes is so limited. Many possible explanations for this might be offered. One is that the art of bark canoe building died early, as the Indians came into contact with the whites, before there was any attempt fully to record Indian culture. The bark canoe is fragile compared to the dugout. The latter might last hundreds of years submerged in a bog, but the bark canoe will not last more than a few decades. It is difficult, in fact, to preserve bark canoes in museums, for as they age and the bark becomes brittle, they are easily damaged in moving and handling. Some small models made by Indians are preserved, but, like most models made by primitive men, these are not to any scale and do not show with equal accuracy all parts of the canoes they represent. They are, therefore, of value only when full-sized canoes of the same type are available for comparison, but this is too rarely the case with the American Indian bark canoes. Today the builders who might have added to our knowledge are long dead. It might be said fairly that those who had the best opportunities to observe, including many whose profession it was to record the culture of primitive man, showed little interest in watercraft and have left us only the most meager descriptions. Even when the watercraft of the primitive man had obviously played a large part in his culture, we rarely find a record complete enough to allow the same accuracy of reproduction that obtains, say, for his art, his dress, or his pottery. Once lost, the information on primitive watercraft cannot, as a rule, be recovered. However, as far as the bark canoes of North America are concerned, there was another factor. The student who became sufficiently interested to begin research soon discovered that one man was devoting his lifetime to the study of these craft; that, in a field with few documentary records and fewer artifacts, he had had opportunities for detailed examination not open to younger men; and that it was widely expected that this man would eventually publish his findings. Hence many, who might otherwise have carried on some research and writing, turned to other subjects. Practically, then, the whole field had been left to Edwin Tappan Adney.