voyage of the paper canoe-第12章
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This was in March； 1867； while the youth was engaged in the manufacture of paper boxes。 Having repaired a wooden shell…boat by covering the cracks with sheets of stout paper cemented to the wood； the result satisfied him； and he immediately applied his attention to the further development of his bright idea。 Assisted by his father； Mr。 Elisha Waters； the enterprise was commenced 〃by taking a wooden shell； thirteen inches wide and thirty feet long； as a mould； and covering the entire surface of its bottom and sides with small sheets of strong Manila paper； glued together； and superposed on each other； so that the joints of one layer were covered by the middle of the sheet immediately above； until a sheet of paper had been formed one…sixteenth of an inch in thickness。 The fabric thus constructed； after being carefully dried； was removed from the mould and fitted up with a suitable frame； consisting of a lower keelson； two inwales； the bulkhead； in short； all the usual parts of the frame of a wooden shell； except the timbers； or ribs； of which none were used the extreme stiffness of the skin rendering them unnecessary。 Its surface was then carefully waterproofed with suitable varnishes； and the work was completed。 Trials proved that； rude as was this first attempt compared with the elegant craft now turned out from paper； it had marked merits； among which were； its remarkable stiffness； the symmetry of the hull with respect to its long axis； and the smoothness of the water…surface。〃
A gentleman； who possesses excellent judgment and long experience in all that relates to paper boats； furnishes me with the following valuable information； which I feel sure will interest the reader。
〃The process of building the paper shell…boat is as follows： The dimensions of the boat having been determined upon； the first step is to construct a wooden model； or form； an exact facsimile of the desired boat； on which to mould the paper skin。 For this purpose the lines of the boat are carefully drawn out of the full size； and from the drawings thus made the model is prepared。 It is built of layers of well…seasoned pine； securely fastened together to form one solid mass； which； after having been laid up of the general outline required； is carefully worked off； until its surface； which is made perfectly smooth； exactly conforms to the selected lines； and its beam； depth； and length are those of the given boat。 During the process of its construction； suitable rabbets are cut to receive the lower keelson； the two inwales； and the bow and stern deadwoods； which； being put in position； are worked off so that their surfaces are flush with that of the model； and forming； as it were； an integral part of it。 It being important that these parts should； in the completed boat； be firmly attached to the skin； their surface is； at this part of the process； covered with a suitable adhesive preparation。
〃The model is now ready to be covered with paper。 Two kinds are used： that made from the best Manila； and that prepared from pure unbleached linen stock； the sheets being the full length of the model； no matter what that may be。 If Manila paper is used； the first sheet is dampened； laid smoothly on the model； and securely fastened in place by tacking it to certain rough strips attached to its upper face。 Other sheets are now superposed on this and on each other； and suitably cemented together； the number depending upon the size of the boat and the stiffness required。 If linen paper is used； but one sheet is employed； of such weight and dimensions that； when dry； it will give just the thickness of skin necessary。 Should the surface of the model be concave in parts； as in the run of boats with square sterns for instance； the paper is made to conform to these surfaces by suitable convex moulds； which also hold the paper in place until； by drying； it has taken and will retain the desired form。 The model； with its enveloping coat of paper； is now removed to the dry…room。 As the paper skin dries； all wrinkles disappear； and it gradually assumes the desired shape。 Finally； when all moisture has been evaporated； it is taken from the mould an exact fac…simile of the model desired； exceedingly stiff； perfectly symmetrical； and seamless。
〃The paper is now subjected to the water…proof process； and the skin； with its keelson； inwales； and dead…woods attached； is then placed in the carpenter's hands； where the frame is completed in the usual manner； as described for wooden boats。 The paper decks being put on； it is then ready for the brass； iron； and varnish work。 As the skins of these boats （racing…shells） vary from one…sixteenth of an inch in the singles； to one…twelfth of an inch in the six…oared outriggers； the wooden frame becomes necessary to support and keep them in shape。 In applying this invention to gigs； dingys； canoes； and skiffs； a somewhat different method is adopted。 Since these boats are subjected to much hard service； and must be so constructed as to permit the occupant to move about in them as is usual in such craft； a light and strong frame of wood is prepared； composed of a suitable number of pairs of ribs； with stem and stern pieces cut from the natural crooks of hackmatack roots。 These are firmly framed to two gunwales and a keelson； extending the length of the boat； the whole forming the skeleton shape of the desired model。 The forms for these boats having been prepared； as already described for the racing…shells； and the frame being let into this form； so that the outer surface of the ribs； stem and stern pieces will conform with its outer surface； the paper skin is next laid upon it。 The skin； manufactured from new； unbleached linen stock； is carefully stretched in place； and when perfectly dry is from one…tenth to three…sixteenths of an inch thick。 Removed from the model； it is water…proofed； the frame and fittings completed； and the boat varnished。 In short； in this class of boats； the shape； style； and finish are precisely that of wooden ones； of corresponding dimensions and class； except that for the usual wooden sheathing is substituted the paper skin as described。
〃The advantages possessed by these boats over those of wood are：
〃By the use of this material for the skins of racing…shells； where experience has demonstrated the smooth bottom to be the best； under…water lines of any degree of fineness can be developed； which cannot successfully be produced in those of wood； even where the streaks are so reduced in thickness that strength； stiffness； and durability are either wholly sacrificed or greatly impaired。 In the finer varieties of 'dug…outs' equally fine lines can be obtained； but so delicate are such boats； if the sides are reduced to three…sixteenths of an inch or less in thickness； that it is found practically impossible to preserve their original forms for any length of time。 Hence； so far as this point is concerned； it only remains for the builder to select those models which science； guided by experience； points out as the best。
The paper skin； after being water…proofed； is finished with hard varnishes； and then presents a solid； perfectly smooth； and horny surface to the action of the water； unbroken by joint； lap； or seam。 This surface admits of being polished as smooth as a coach…panel or a mirror。 Unlike wood； it has no grain to be cracked or split； it never shrinks； and； paper being one of the best of non…conductors； no ordinary degree of heat or cold affects its shape or hardness； and hence these boats are admirably adapted for use in all climates。 As the skin absorbs no moisture； these boats gain no weight by use； and； having no moisture to give off when out of the water； they do not； like wooden boats； show the effect of exposure to the air by leaking。 They are； therefore； in this respect always prepared for service。
The strength and stiffness of the paper shells are most remarkable。 To demonstrate it； a single shell of twelve inch beam and twenty…eight feet long； fitted complete with its outriggers； the hull weighing twenty…two pounds； was placed on two trestles eight feet apart； in such a manner that the trestles were each the same distance from the centre of the
