segunda-feira, 3 de fevereiro de 2020

A construção do Barco do Mar por Paul Johnstone

Da Costa [Henrique Ferreira da Costa, Mestre de Ribeira em Pardilhó] has only two daughters and no apparent successor to take over his boat-building business in the little village of Pardilhó near Aveiro. 

(Instantaneos do sr. Alberto Lima)
Costa de Caparica, Alberto Carlos Lima, pescadores puxando uma embarcação para terra, década de 1900.
Arquivo Municipal de Lisboa

The incompleteness and briefness of this attempt to record his methods is due partly to our shortage of time there, partly to the interpreter who was willing but uninformed about boats, and partly because at the time da Costa was working on a smaller related, but not identical, type to the "xavega".

The wood he uses for a "xavega" is pine, which grows abundantly in the district, though now frequently mixed with intrusive eucalyptus.

Costa da Caparica, Meia-lua, Paul Johnstone.
Portuguese fishing boats, Country Life Magazine, 1966

Before construction begins, the strakes are sawn and bent to the right curve. This is done simply by wetting them, putting them under tension and then lighting a fire of pine shavings underneath. For the frames, pine trunks are selected with a single root growing to approximately the right angle left on them.

Unlike the smaller boats which are built in the boatyard itself, the "xavegas" are built in the open air near their launching place, a dock which leads on to one of the great lagoons north of Aveiro, the working area of some of the almost equally remarkable "moliceiros" or seaweed-gathering craft. 

The small boat we saw under construction had apparently no particular name other than "barco" the Portuguese for boat. Senhor da Costa seemed to feel that naming the different sorts of boat was a matter for boatmen rather than the builder. Like the "xávega" (or "saveiro") and all the other local boats the "barco" we saw building had no keel.

The process of building begins with a line of posts (which would be called keel blocks if there were a keel) to support the centre-line plank of the boat’s bottom. In the case of the "xávega", these are under the centre line. The tops of these posts follow, in height from the ground, the rocker of the bottom of the craft.

Início da construção do Saveiro, Paul Johnstone.
An unusual portuguese fishing boat

br /> The ones at bow and stem are of course much higher than the others because of the curve of the bottom. The centre-line plank is lightly nailed to each of these blocks with a single iron nail. Rather surprisingly, the bottom of the boat is not completed at this stage. 

Gaps are left either side between the centre-line planks and the outer bottom planks. Next, the boat’s centre-line is drawn on the bottom plank, and ticked off at equal intervals to show the positions of the frames. This is done with a measuring rod ("pau dos pontos" in Portuguese) on which are marked the distances from the centre-line to the boat’s hard chine at each frame.

Da Costa has one of these rods for each boat he builds. One face of it has these dimensions for the after frames, numbered from 1 (for the after-most) to 8. Another face carries the dimensions of the forward frames, numbered in a similar manner.

So the bottom of the boat is marked out. A long, light batten (about a one centimetre square in cross-section) is bent round the pencil points, and a pencil line is drawn to represent the chine of the boat either side. The bottom is now sawn to shape.

Meanwhile the frames have been prepared. One adjustable mould governs the shape of all the frames except one at each end. It is the only other measuring instrument used besides the rod. Each frame is in two pieces. The larger L-piece includes almost a complete floor timber. The smaller piece is little more than an upright or futtock. The first frame to be put in place is the forward one.

Costa da Caparica, Cavername do Meia-lua, Paul Johnstone.
Paul Johnstone, The Sea-Craft of Prehistory, 1988

The larger pieces are built into the boat next, with uprights alternately to port and to starboard, making a pleasing pattern. The upright portions are left overlong and unfinished. The bend of each frame is in fact lined up to the outer bottom plank, i.e. to the chíne.

The curve of the upright portions is drawn on prepared pieces of timber by follo-wing the line of the mould with ink. The curves are then sawn along the lines by two boys with a bow-saw, using a trestle structure instead of a saw-pit.

Costa da Caparica, Cavername em "L", Paul Johnstone.
To illustrate the monuments

We observed the lads sawing a considerable bevel by eye. Da Costa explained that an adze [enxó] is used as necessary to finish off the bevel after the frames have been set up.

Next comes the top strake. With a "xavega" Da Costa has a timber offset about five metres long for the top strake, because of its very pronounced sheer.

After first being held in place with clamps and small iron nails, the top strake, like the other planking is permanently secured with treenails.

Costa da Caparica, Cavilhas em madeira, Paul Johnstone.
To illustrate the monuments

These treenails are made from roughly-shaped pieces of pine wood sawn from a slab. Da Costa then finishes them with a curious tool rather like a bill-hook. He does this by inserting one in a hole in a wooden roundel and then pressing treenail and roundel against his chest with one hand, leaving the other free for the shaping.

All is done by eye and he leaves a considerable head on one end and slightly slopes off the point at the other. No wedges or inserted metal nails are used to secure the treenails in place. Presumably, being pine, they are soft enough to be compressed when hammered home and then expand enough, especially when wet, to make a tight fit.

Da Costa used an electric drill to make holes for his tree-nails, but he was quick to demonstrate the auger which he had apparently used until recently. The holes are drilled, and the treenails then driven from the outside, dry, without any grease or other preparation. A lad using a saw or an adze cuts off the surplus flush with the inner face of the frame.

Once the top strake is secured in place the frames are trimmed down to its upper edge. The final shape of the boat is now apparent.

The next step is to scarf in the uprights which complete each frame. A simple 45oscarf is used, secured, in the small boat, with a single treenail and in the "xavega" with a quincunx of treenails.

The side planking is completed next, and then a gunwale, i.e. a length of wood running inside the frames level with the top strake. All the side strakes are horizontal, even to the small ones high up in the bow in the "xavega".

This combination of extravagant sheer with horizontal planking is a striking feature of the "xavega" and also of other local craft, the "meia lua", the "moliceiro" and the "mercantel". This combination also appears outside Portugal in the Venetian gondola and the boats of Malta.

Finally, the boat is detached from the blocks and rolled on its side for the remaining bottom planking to be put in place and secured.

The caulking is of hemp, inserted with a normal caulking iron. Pitch is also used on top of the caulking in the seams in the bottom. Five straps round the bottom and sides of the bow and stern respectively, and the thole-pin plates are of metal but, like the other metal fittings, seem after-thoughts or recent additions.

There are also two metal cruciform straps each side which hold the hauling rings for the oxen and two rings on the stem for the same purpose. Metal bolts are used to fasten these but da Costa was at pains to explain to us that metal fastenings were much less satisfactory than treenails, as they had no elasticity and so were more liable to snap. In all, he uses about 1,600 treenails in one ‘xavega’, whose working life is estimated to be about eight to ten years.

Since the planking is bent round and then secured to the larger part of each frame first, and the smaller part of the frame inserted after this has been done, the "xavega" can claim additionally to be built in neither true skeleton nor shell-fashion.

An example of one of these craft, the "San Paio", as has been said, can now be studied in detail at Exeter, and a BBC TV ‘Chronicle’ film was made of one in use at Torreira, which can also be viewed at the Museum. But unfortunately time and cost limited the amount of filming of the construction.

Saveiro meia-lua da Torreira, "S. Paio", Exeter Maritime Museum (1969-1997).
eBay

Hence these brief notes, which we hope may encourage more people to contribute to the records of traditional craft, many of which will shortly disappear from use for ever. It all seemed to us that the "xavega" reinforced the arguments of Throckmorton and others that surviving practices tell archaeologists a good deal that it is impossible to deduce from remains alone. (1)


(1) Paul Johnstone/A. F. Tilley, An Unusual Portuguese Fishing Boat, Mariner’s Mirror, Vol 62, no. 1, 1976, p. 15 e seg. cf. Hernâni A. Xavier, A Ascendência dos barcos tradicionais portugueses, 2008

A construção do Barco do Mar (apontamentos diversos):
Paul Johnstone, The Sea-Craft of Prehistory, 1988
Hernâni A. Xavier, A Ascendência dos barcos tradicionais portugueses, 2008
Octávio Lixa Filgueiras, Barcos de Portugal, obras selecionadas
Senos da Fonseca, Embarcações que tiveram berço na laguna
O meu barco da Arte Xávega
Terras de Antuã - Histórias e Memórias do Concelho de Estarreja
Arte Xávega em Espinho

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