The Bark Canoes and Skin Boats of North America

Chapter Eight
TEMPORARY CRAFT

Use of temporary craft seems to have been confined to the Indians, who for the most part built them of bark, although some tribes used skins. However, very little in the way of information exists on the forms used by the individual tribes, for early travelers did not always have opportunities to see these emergency craft, and when they did they rarely took the trouble to record their construction and design.

Bark Canoes

There is ample evidence to support the belief that a great many of the tribes building birch-bark canoes also used temporary canoes of other barks such as spruce and elm, as has been mentioned in earlier chapters. Invariably, the qualities of these other barks, particularly spruce, were such that their use was often somewhat more laborious and the results less satisfactory than with birch; but the necessities of travel and the availability of materials were controlling factors, and with care spruce bark could be used to build a canoe almost as good as one of birch bark. The forms of these canoes do not appear to have been as standardized as the tribal forms of the better-built bark canoes; rather, the model of the temporary canoe was entirely a matter to be decided by the individual builder on the basis of the importance of the temporary canoe to his needs, the limitation on time allowed for construction, and the material available.

The reasons for using substitute material are fairly obvious. In forest travel it was not always possible or practical to portage a canoe for a long distance simply to make a short water passage somewhere along the route. War parties and hunters, therefore, often found it necessary to build a temporary canoe, one that could be utilized for a limited water passage and then abandoned. Since such a limited use did not warrant expenditure of much time or labor on construction, the canoe was prepared quickly from readily available material and in order to meet these requirements many Indian tribes developed canoe forms and building techniques somewhat different from the more elaborate construction using birch or spruce bark.

It is obvious that much time and work could be avoided by use of a single large sheet of bark that was reasonably flexible and strong. But many of the barks meeting this specification had a coarse longitudinal grain that split easily, so forming a canoe by cutting gores was out of the question. This difficulty was avoided by folding, or "crimping," the bark cover along the gunwales at two or more places on each side of the canoe; this permitted the bottom to be flattened athwartships and the keel line to be rockered, both desirable in a canoe.

The problem of closing the ends also had to be solved. This was done by clamping the ends of the bark between two battens and, perhaps, a bark cord as well, and then lashing together the battens, bark ends, and cord with wrappings of root thongs. Cord made from the inner bark of the basswood and other trees could also be used for this purpose. The ends of the canoe could then be made watertight by a liberal application of gum or tallow, while grass, shavings, moss, or inner bark mixed with gum or even clay could be used to fill the larger openings that might appear in hurried construction.

Obviously, a simple wood structure was required by the specifications. Therefore, the gunwales were usually made of saplings with their butts roughly secured together or spliced. This allowed length to be obtained without the necessity of working down large poles to usable dimensions, a laborious and time-consuming undertaking with primitive tools. The thwarts were commonly of saplings with the ends cut away so that the thin remainder could be wrapped around the main gunwales and lashed underneath the thwarts inboard. Ribs were usually of split saplings, but there is some evidence that in very hurriedly built canoes the whole small sapling was used. The kind of sheathing employed in these canoes during the pre-Columbian era is a mystery. It would be quite unlikely that time was taken to split splints such as were used in the late elm-and spruce-bark canoes, when steel tools were available. The writers believe that for small canoes it may have been the practice to use a second sheet of stiff bark inside the first and extending only through the middle two-thirds of the length, across the bottom and up above the bilge but short of the gunwales. This, with the ribs and a few poles lashed to each rib along the bottom, would have given sufficient longitudinal strength and a stiff enough bottom for practical use. However, in large canoes of the type reputedly employed by Iroquois warriors, a stronger construction seems necessary, and these canoes may have had a number of split or whole poles lashed to the ribs along the bottom.

With small variations in details, the general construction outlined above was employed by many North American Indians for building temporary canoes for emergency use. In at least one case, however, it was also used in canoes of somewhat more permanent status within the boundaries of the powerful Iroquois Confederation. On large bodies of water within their territory, the Iroquois used dugouts, but for navigating streams and for use in raiding their enemies they employed bark canoes. While some birch bark was available there, it was probably widely scattered; therefore these great warriors used elm or other bark for their canoe building.

Early French accounts show that the Iroquois built bark canoes of greater size than ordinary; Champlain wrote that their canoes were of oak bark and were large enough to carry up to 18 warriors; later French accounts, as we shall see, indicate that the Iroquois used even larger canoes than these. Champlain may have been in error about the Iroquois use of oak bark, as suggested earlier (p. 7), for experiments have shown that the inner bark of this tree is too thin and weak for the purpose; the canoes Champlain saw may have been built of white or red elm bark. The barks of the butternut, hickory, white pine, and chestnut might also have been employed, as they were usually suitable.

It was noted by the early French writers that the Iroquois built their bark canoes very rapidly when these craft were required by a war party in order to attack their enemies or to escape pursuit. In one case at least the canoes for a war party were apparently built in a single day. This was accomplished, it seems, by the excellent organization of their war parties, in which every man was assigned a duty, even in making canoes.

When it was deemed necessary to build a canoe, certain warriors were to search out and obtain the necessary materials in the order required for construction. To do this effectively, they had to know the materials in order of their suitability for a given purpose, for the most desirable material might not be available at the building site. Other warriors prepared the materials for construction, scraping the bark, making thongs, and rough-shaping the wood. Others built the canoe, cutting and sewing the bark, and shaping and lashing the woodwork. These duties, too, required intimate knowledge of the different materials that could be used in canoe construction. It would be natural, of course, to find that the methods used to construct a temporary craft for a war-party would also be employed at home by the hunter or fisherman, even when a rather more permanent canoe was desired. These were smaller craft and easily built. Only when a long-lasting watercraft was desired would the bark canoe be unsatisfactory; then the dugout could be built. The early French observers agree that though the Iroquois occasionally used birch-bark canoes, these were acquired from their neighbors by barter or capture and were not built by the tribesmen of the Confederation.

The details of the construction of elm canoes (and of other bark than birch) by the Iroquois are speculative, since no bark canoe of their construction has been preserved. This reconstruction of their methods is, therefore, based upon the incomplete accounts of early writers and upon what has been discovered about the construction of spruce-and elm-bark temporary canoes by other Eastern Indians.

In view of what has been reported, it must be kept in mind that the construction was hasty and that a minimum of labor and time was employed; hence, the appearance of the elm-bark canoe of an Iroquois war-party had none of the gracefulness that is supposed to mark the traditional war canoe of the Indians. The ends are known to have been "square," that is, straight in profile, and the freeboard low. The use of saplings for the gunwales would cause an uneven sheer, and its amount must have been small; the high, graceful ends seen in some birch-bark canoes did not exist in the Iroquois model. The rocker of the bottom profile was not a fair curve, but was angular, made of straight lines breaking under the folds, or "crimps," in the bark cover at the gunwales. The amount of bark in each crimp and the location of the crimps fore-and-aft would determine the shape of the bottom profile and the amount of rocker, as well as the flatness of the bottom athwartships in the midbody. It appears that two crimps to the side were employed in most of these canoes, but perhaps more, say four to a side, might have been employed in a very large canoe. The tendency in forming these canoes must have been toward an almost semicircular midsection, a condition which would have produced an unstable craft if not checked.

The early French writers agree that the canoes of Iroquois war parties were sluggish under paddle. This was due to the fact that the hull form of these canoes was not good for speed, and also because the bulges at the bottom of the crimps caused them to be markedly unfair at and near the waterline. This handicap in their canoes may have been an inducement for the Iroquois to waylay their victims at portages when the travellers were usually spread out and easily cut down while burdened with goods. The Algonkin tribes countered by moving in very large numbers when within striking distance of Iroquois raiders. Hence there were very few recorded instances of battles in canoes; these took place only when sudden meetings occurred without preparation on either side, such as when war parties surprised canoemen in narrow waters. The shortcomings of their canoes did not seriously affect the deadliness of the Iroquois warriors, for their usual practice was to raid in winter, when they could travel rapidly on snowshoes and surprise their enemies in winter camps wholly unprepared for defense, a most pleasing prospect for the attacking warrior.

It would be a mistake, however, to assume that these factors made the Iroquois poor canoemen; the French repeatedly stated that they were capable in handling their craft and ran rapids with great daring and skill, showing that the apparently crude and weak elm-bark canoes were far better craft than they first appeared.

The theory that the Iroquois type of canoe was very like the emergency or temporary elm-and spruce-bark canoes of neighboring tribes is supported by some statements of the early French writers, as well as by a comparison of the rather incomplete descriptions of Iroquois canoes by later travellers with what is known about the spruce and other temporary bark canoes used in more recent times by the eastern Indians. M. Bacqueville de la Poterie, writing of the adventures of Nicholas Perrot in the years 1665 to 1670, tells of an instance in which Perrot's Potawatomi mistook the emergency canoes of some Outaouais (Ottawa) for Iroquois canoes.

LaHontan (1700) gives some general information as well as specific opinions on the speed and seaworthiness of Iroquois canoes, saying that—

LaFiteau, writing before 1724, stated definitely that the Iroquois did not build any birch-bark canoes, but obtained them from their neighbors, and that the Iroquois elm-bark canoes were very coarsely built of a single large sheet of bark, crimped along the gunwales, with the ends secured between battens of split saplings. He noticed that the gunwales, ribs, and thwarts were of "tree branches," implying that the bark was not removed from them. The most detailed description was by a Swedish traveller, Professor Pher Kalm, who gave extensive information on the construction of an elm-bark canoe in 1749; this account is particularly useful when interpreted in relation to the spruce-and elm-bark canoes of the eastern Indians. It is upon the basis of Kalm's account that the procedures used to build an Iroquois war canoe have been reconstructed.

The bark most favored by the Iroquois was that of the white elm. Next most favored was red elm, and then other barks—certain of the hickories and chestnut are mentioned in various early references. It was necessary to find a tree of sufficient girth and height to the first limbs to give a sound and fairly smooth bark sheet in the length and breadth required. If possible the bark was stripped from the standing tree; even after steel tools were available, felling was avoided for fear of harming the bark. Great care had to be taken in the operation, to avoid splitting or making holes in the bark, and often two or more trees had to be stripped before a good sheet of bark was obtained. In warm weather the bark could be removed without much difficulty, but in the spring and fall it might be necessary to apply heat; this was apparently done by means of torches or by the application of hot water to the tree trunk.

When the bark was removed from the tree, the rough outer bark was scraped away; if the builder was hurried this scraping was confined to the areas to be sewn or folded. The bark was then laid on a cleared piece of ground, the building bed, with the outside of the bark up, so that it would be inside the finished boat. The building bed does not appear to have required much preparation; apparently not raised at midlength, it was merely a plot of reasonably smooth ground, located in the shade of a large tree if building was to be done in summer.

It is not wholly clear from the descriptions whether the gunwales were shaped before or after being secured to the bark. However, extensive experiments in building model canoes show very plainly that it would be easiest to assemble the main gunwale frame and use it in building, after the fashion of eastern birch-bark canoe construction. With the main gunwales assembled, the stakes would be placed on the bed, the bark replaced, the frame laid on it and weighted, and the stakes then redriven in the usual way and their heads lashed together in pairs.

Each gunwale was formed either of two small saplings or of split poles, with the butts scarfed at the canoe's midlength. The canoe of an Iroquois war party would probably have gunwales of split saplings so that inwale and outwale for half the length of one side of the canoe would be from a single pole; this would allow the flat sides to be placed opposite one another, on each side of the edge of the bark, to form a firm gunwale structure. However, when a rather permanent craft was being built, the poles might be split twice, or quartered, to give pieces to make half of the gunwales of a canoe; these too might be worked nearly round before assembly.

That the gunwale joints were scarfed is reasonably certain. The elm-bark canoes of the St. Francis Indians are known only from a model, as are the spruce-bark hunters' canoes of the Malecite, but the testimony of old St. Francis and Malecite builders support the evidence of the models; therefore it is probable that the use of scarfed gunwales was common in these canoes, and, hence, also in the canoes of the Iroquois, who dwelt nearby. The manner of scarfing is not certain. Probably the butts were snied off so that the lap would be flat face, as was usual in the Malecite spruce-bark canoes of this same class. The butts were secured together by lashings—apparently let into shallow grooves around the members. In a very hastily built canoe the butts might be merely lapped for a short distance, one butt above the other, and lashed; this, of course, would make a jog in the sheer, but do no harm, as the jog would occur in both inwale and outwale, and the bark would lay up between these and be trimmed to suit.

The thwarts were described in old accounts as very small saplings, or tree branches, with their ends sharply reduced in thickness so that they were thin and pliable enough to be bent around the gunwales and brought inboard under the thwart, as done by some Kutenai in the West (see p. 169). The thwart ends might be lashed or, as in some eastern spruce-bark canoes, brought up through a hole in the thwarts to the top where it could be jammed or lashed. In the Iroquois canoe it seems probable that the thwart ends passed around the main gunwales only and were secured under the thwarts for, as noted, the evidence strongly suggests that the main gunwale members were preassembled, a procedure that requires the thwarts to be in place. In the small hunters' canoes, however, some eastern builders apparently put in a temporary spreader in place of a single thwart until the canoe was completed to the point where the outwales were in place, then the thwarts were added, the ends passing over and around both inwale and outwale and through the bark cover below, to the underside of the thwart.

One requirement in building these canoes was to crimp the edges of the bark at the gunwales in such manner that the bottom of the canoe would be rockered and at the same time would be moulded athwartships. First steps in the process were to set into the building bed two heavy stakes on each side of the stems, a little inboard of the ends, and to tie the heads of each pair together with a heavy bark cord or a rawhide thong. Then a sling was made, the bight of which went under the bottom of the bark cover near its ends, and the ends of the sling were made fast to the heads of the stakes. By taking up on these slings, the ends of the bark cover were sharply lifted and then the folding of the bark along the gunwales could be easily accomplished, as they then formed naturally, without strain. The crimps were commonly located a fourth to a fifth the length of the canoe inboard of the ends, about where the end thwarts would be located. In small hunters' canoes the end thwarts were often replaced by twisted cords across the gunwales, but in the large Iroquois canoes there were probably five or seven or perhaps as many as nine thwarts according to length.

The ends of the gunwales were simply lashed together with cords or thongs in shallow grooves to prevent slipping. They were raised by a small inside post, its heel placed on the bark near the stem and its head brought under the gunwales, so that it served the purpose of a headboard in sheering the gunwales.

The procedure in building to this point, then, appeared to follow the general plan used in birch-bark construction. Next, the stakes were redriven in the bed around the gunwale frame, which was weighted on the bark with stones, and the sides of the bark cover were brought upright. Apparently only a few stakes were considered necessary—three or four to a side and two pairs of end stakes to raise the stems. The gunwale frame was then lifted to the required height of side and lashed temporarily to the side stakes, the ends of the bark cover were creased to form bow and stern, and the headboard posts were inserted to support the ends of the inwales and to sheer the canoe. Before this, of course, the ends of the bark cover had been raised by means of the slings to the end stakes.

The outwales of split saplings were now put into place, with the edges of the bark cover lashed between the flat surfaces of the inwale and outwale, the gunwales having been assembled with the flat face of the longitudinal members outboard. The lashings were in small groups spaced 5 to 7 inches apart so as not to split the bark, and these not only secured the bark in place but also held the inwales and outwales tightly together, to clamp the edges of the bark cover. At the thwarts, the outwales were notched on their inboard face to allow them to come up against the bark pressed against the face of the inwales (in some eastern canoes the bark cover was notched at the thwart ends to lay up smoothly there, and this may have also been done in the Iroquois canoes). In placing the outwales, the crimps were carefully formed and held by the clamping action of the inwale and outwale, and reinforced by a lashing through the crimp or by two lashings close to the sides of the fold. The fold of the bark forced the outwale away from the inwale, and although this was counteracted to some extent by the lashings, the gunwales were unfair at these points. The crimps were formed so that the maximum fold in the bark took place at the gunwales; below this the fold tapered away to nothing, ending low in the side with an irregular bulge in the bark. Such a bulge could only be avoided by goring, which is impractical with elm, pine, chestnut, or hickory barks.

The ends of the canoe were closed, as has been mentioned, by use of split-sapling battens on the outside of the bark. The Iroquois and some other builders also employed at the stems a thong or a twisted cord made of the inner bark of some such tree as the basswood; this was wrapped around the ends of the bark cover abreast the headboard posts inside the canoe, so that the lashing stood vertically. Then the split battens were placed on each side of the bark cover, just outboard of the cord, and the whole was secured by a coarse spiral lashing of root or rawhide, which passed inboard of the cord lashing and the headboard post, as well as around them and the split battens outside of the bark cover. Some builders apparently added a split-root batten over the edges of the bark cover, as a sort of stem-band; this was secured by the turns of the stem closure lashing, which passed around them as well as the edges of the bark and the split side battens. It can be seen that this closure formed a strong stem structure. Watertightness was insured by merely forcing clay into the stems from the inside, or by forcing in a wad of the pounded inner bark of a dead red elm which would swell when damp. Still other methods included the use of grass or moss impregnated with warm tallow from the cooking pot. If available, the stems would be liberally smeared with spruce or other gum, of course.

While the ribs were customarily tree branches or small saplings, in some canoes the saplings were split and bent so their flat face was against the bark. In the East, hunters' canoes were often given the lath-like ribs of the birch-bark canoes, for when steel tools became available such ribs were easily made during the winter for use in the spring, when the temporary canoe would be needed.

According to the early reports, the ribs were placed some 6 to 10 inches apart in the bark cover, with the heads forced under the inwales against the bark, and were supported there by the outwales as well. No mention is made of any sheathing; Kalm refers to a piece of bark and some saplings or tree branches laid over the ribs to protect the bottom inboard. In the large Iroquois canoes it would have been possible and practical to employ a piece of bark inside the main bark cover, as noted on page 213; this inside piece needed to be only long enough to reach to the end thwarts, or abreast the crimps, and wide enough to cover the bottom and bilges up to 3 or 4 inches short of the inwales. With the ribs over this inner sheet, a stiff bottom would result. In a long canoe, split poles could be laid lengthwise inside the bottom of the canoe and fastened there by lashing them to a few ribs; these would serve to protect the bottom in loading and to stiffen the bark cover. However, in a small canoe the stiffness of elm bark when the rough outside layer was not fully scraped off would make sheathing of any kind unnecessary, and the bark mat inside the ribs, mentioned by Kalm, would be sufficient.

The difficulty in reconstructing the building methods of the large Iroquois canoes on the same basis is that Kalm's description is of a rather small canoe; the information on the temporary canoes of the eastern Indians also deals with short craft. It is evident, however, that poles were not usually placed between the bark and the ribs, as in temporary skin canoes built by Indians. It is also apparent that splints were not used by the Iroquois for sheathing large canoes.

The ends of the outwales in the Iroquois canoes seem to have been secured by snying them off on the outside face and holding these thin ends by the cord around the ends, as well as by the closure battens of the stems. In some eastern canoes, notably the elm-bark canoes of the St. Francis, the outwale ends projected slightly outboard of the stems and were lashed across them by a simple athwartship lashing which passed through the bark cover and under and over the lashing at the inwale ends.

In a drawing of an Iroquois canoe made about 1849, the cord around the stems is shown together with the outside stem battens and lashing; the ends of the outwales are apparently under the cord and perhaps under the stem battens. The stem batten is in one piece sharply bent under the stems in U-form. The end lashing shown seems to be in groups and the bottom, for a little distance inboard of the stems, is also shown as lashed. Three thwarts are shown. It may be that this drawing was made not from a full-size canoe but from a model, for the proportions are obviously incorrect. This possibility casts some doubt on the picture as evidence of the building practices, for in Indian-built models simplified construction details not used in actual canoe building are often found.

According to early accounts and the statements of eastern Indians, these emergency canoes were often heavy and unsuitable for portaging. By 1750, at least, the Iroquois were using blanket square-sails in their elm-bark canoes.

Skin Boats

Among the other forms of temporary or emergency canoes used by North American Indians, the most widespread was some form of skin boat. These would not require description here were it not for the fact that the Indian skin boats were usually built by bark-canoe methods of construction rather than by methods such as used by the Eskimo. To build their skin boats—kayaks and umiaks—the Eskimo first constructed a complete framework, and this was then covered with skins sewn to fit. This process of building required a rigid framework capable of not only standing without a skin covering but also of giving both longitudinal and transverse strength sufficient to withstand loading, without the slightest support from the skin covering. Hence, the framework of the Eskimo craft was made with the members rigidly lashed and pegged together. The majority of Indian skin canoes, however, required the covering to hold the framework together, as in a birch-bark canoe. An example is the Malecite skin-covered hunters' canoe. According to available information, the Malecite hunter would leave two or three moose skins on stretchers for use in building a skin canoe in the early spring. Sometimes the hair was removed from the hides and sometimes it was not. Spare time during the winter hunt might be spent in preparing the wooden framework, but if this were not done the delay would not be very great.

The gunwale frame was first made of four small sapling poles roughly scarfed at the butts. From a small sapling a middle thwart was made in the manner of the elm-bark canoe thwarts, the ends tapered enough to allow them to be wrapped around the gunwales and secured under the thwart by lashings. The ends of the gunwales were merely crossed and lashed. Where end thwarts would be placed, it was usual to use a cross tie made of twisted rawhide or cords of bark fiber. Holes were then drilled at intervals in the underside of the gunwale to take the heads of the ribs. Stem-pieces about 3 feet long were prepared of short saplings and bent to the desired profile; one builder used a full-length keel-piece, instead of the short stem-pieces. The ribs were usually of small saplings that could be bent green without the use of hot water. For sheathing a number of small saplings were also gathered, and from them were made poles in lengths about equal to three-quarters, or a little more, of the intended length of the canoe, which would be determined by the size of the skins available. The average canoe was about 12½ feet long, roughly 40 inches beam, and 14 to 19 inches in depth.

The skins were sewn together lengthwise, lapped about 6 inches or a little less, and secured by a double row of stitching. If the hair had not been removed, it had to be scraped away along the sewn edges. In such a case the hair would usually be on the outside of the finished canoe. Also, before work was started on assembling a canoe, the skins were worked pliable, and tallow and gum were accumulated.

When an emergency canoe was ready to be assembled a smooth place was prepared; either an open bit of ground or the floor of the hunter's hut, if large enough, might be used. The outlines of the gunwales were fixed by a few stakes temporarily driven around it and then pulled up. The skins were then laid on the bed and the gunwale frame placed on them and weighted with stones. Then the skins were left to dry for awhile until they became somewhat stiff; the proper condition was indicated by the curling of the edges.

When the skin was sufficiently stiff, the gunwale frame was lifted and temporarily secured to the stakes redriven in the bed, the sides of the skin were turned up, the skin was gored, and sometimes the ends of the gunwales were sheered up slightly at the end stakes; this latter was not always done, for in some canoes the sheer was quite flat.

The skins were now trimmed to the sheer of the gunwales and the edges lashed to these members with rawhide, the gores also having been sewn. Next the stem-pieces were put into place and the stem heads lashed inside the apex formed by the ends of the gunwales. Some ribs were then bent and forced down on the stiff skin cover, the rib ends being worked into the holes prepared for them on the underside of the gunwales. These ribs usually stood approximately square to the curve, or rocker, of the bottom. Now the skin could be trimmed to the stem profiles and sewn. The stitching was usually done so as to be outside the stem-pieces, with an occasional turn going around inside them to help hold the structure in place. Some builders first put in the stems temporarily and then trimmed the skins to match; after this was done the stem-pieces were removed to allow easy sewing. When they were replaced and secured permanently, a few more stitches were added along the stems to secure the woodwork.

The next step was to sheath the canoe inside with the small poles; these were placed a few inches apart transversely and their ends worked under the most inboard of the ribs on the stem-pieces, then held in place, while the necessary adjustments were made, by a few temporary ribs. Then the ribs were forced into place, one by one, each prebent to the desired section, just as in birch-bark canoe construction. In this final shaping, the skin cover might have to be wetted again to soften the material and to allow stretching. The seams were then payed with gum or tallow, and the canoe was ready for launching.

The description is for canoes of minimum finish; builders often used split and shaped gunwales, split ribs, and splint sheathing if these could be prepared during the winter. The construction of a skin canoe was not a specialized process in which a hunter consistently built this one type; the selection was determined by natural conditions. If he were to come out of the woods too early in the spring to make the construction of a spruce-bark canoe easy, then he would resort to skin construction; the statements of old Malecite hunters leads to the conclusion that as emergency craft they used spruce-bark canoes most often.

Perhaps the most primitive of the skin boats built by the North American Indian was the so-called bull-boat of the Plains Indians. These were not canoes but coracles—bowl-shaped and suitable only for use on streams, where ferrying would be the main requirement. The boats were covered with buffalo-hides and their framework was usually made of the willow shoots found along the streams. The framework followed, to some extent at least, the basketwork principle, a circular gunwale or rim being used. The ribs were set in two groups, half at right angles to the other half in very irregular fashion. This construction formed a sort of rough grating in the bottom. The ribs were lashed together with rawhide and apparently the craft was built up on the skin as were the Malecite skin canoes. Battens in circular form were used on the sides to fair the cover. The form of the bull-boat varied somewhat among individual builders; sometimes it assumed almost a dish shape with shallow flaring sides, but more commonly the sides were nearly upright; the bottom was always flat, or nearly so. These bull-boats appear always to have been small. Judging by the examples preserved, a bull-boat 5 feet over the rim or gunwale, or made of more than one skin, was extremely rare, and most examples are nearer 4 feet and built on a single skin. Many were too small to carry a person; these were intended to be loaded with cargo to be kept dry and towed by a swimmer. When they were large enough to be paddled, the paddler worked over the "bow," as in a coracle. Probably all the Plains Indians living near streams once used the bull-boat, but existing records show only the Mandan, Omaha, Kansas, Hidatsa, and Assiniboin to have used it. The Blackfoot (Siksika) and Dakota are said to have used some kind of a skin boat in which their tepee poles were employed as a temporary frame, but nothing is recorded of their form.

The use of spruce bark as a building material in the Northwest and throughout the extreme northern range of the birch-bark canoe has been discussed in earlier chapters (pp. 155 to 158). In these areas, the emergency canoe was usually built of caribou skin. On the Alaskan coast seal skin may also have been used, but generally it was used for the permanent kayak-type canoe and not for a hastily built temporary craft. The caribou-skin canoe was also built as a permanent type, in either kayak form or somewhat on the model of the spruce-or birch-bark canoe of the area. However, although references to temporary craft covered with caribou skin exist in early accounts of the fur trade, there is no record of their form or details of their construction. Early in the present century some of the Indians of the Mackenzie River country built skin canoes much like the modern canvas-covered freight canoes. Also, some of these skin canoes were built so that they resembled York boats or the whaleboats of the white man. No observer has described the methods used to construct the emergency canoe of the Northwest; we do not know whether they resemble those used in the Indian bark canoe or in the Eskimo skin boat.