so, THE KEEL is LAID. A baulk of teak, shaped to match templates taken off the full size lines plans drawn out on the loft floor. It rests on blocks so set that they will bring the boat up to a convenient height for building. The keel slopes gently from aft forward at the designed depths measured down from the horizontal datum waterline, the line at which the boat is designed to float.

Now the rest of the boat's centreline structure can be assembled from the baulks and laminates, shaped and waiting.

But first, a building batten is fixed in place in the rafters high above the boat. This is a batten running along the centreline, above the keel, the full length of the boat, on which is marked the exact position of stem and stern, each station, each bulkhead, each timber; in fact it carries every fore and aft measurement which will be needed in building.

From it the boatbuilders, using a plumb line, will be able to determine the position of every transverse member as construction progresses.

Stemhead, stempost, stem apron, fore deadwood, keel (with the hog above it), after deadwood, stern knee and sternpost —all are bolted together, bedded down, to build up the backbone structure. Great strain will be placed on keel and hog during building, so they are held down from above by three vertical shores and from below by strainers bolted to the floor.

Next come the moulds round which the longitudinal members—stringers, deck shelf and gunwale—will be shaped.

The moulds are temporary; after the hull is planked and they have done their work, they will be taken out.

There is a mould at each of the ten stations equidistant along the length of the boat. The first to be fitted into place is station 5, halfway down the boat; square to centreline and datum waterline, plumb upright and foursquare.

Then the remaining moulds are set up; for those forward of station 5, the station position, established by plumb line from the building batten, is at the forward side of the mould; for those aft of station 5 the station point is at the aft side of the mould. Thus placed their square edges will not impede the curve of the hull.

This is another crucial stage of building, and measurements will be checked and counterchecked to make sure that each mould is accurately placed and square in both planes. On them depends the fair curve of the hull. Once in place they are braced with diagonal timbers to a beam in the roof of the building shed.

When building a lifeboat hull, rather than that of an ordinary motor vessel, there are the extra complications resulting from the propeller tunnels; towards the stern the planking is not continuous but is landed on the tunnel cant which forms the outboard edge of the tunnel.

The forward part of the cant, a straight run, is made of solid mahogany, but at the after end it has to curve up and inboard to the stern; that part is built up of laminates glued and clamped together in position on the underside of the frames.

Notches are now cut out of the moulds to take the oak longitudinals, which will be steamed and bent round them to take up the fore and aft curve of the hull.

Then come the oak timbers—the boat'sribs—once again steamed to take up the transverse curve from hog to stringers, deck shelf and gunwale.

The skeleton of the hull is now ready to take the skin—the planking..