This is a long-established technique across the globe for making strong, smart and comfortable shoes. The cross-section diagram on the left shows what you’d see if you chopped the Loake Stamford on the right across the stitching of the toe cap (don’t try this at home!). The upper, insole (via the ribs) and the welt are stitched together first, on the last. The rib can be seen more clearly below – it’s the white ridge with a serrated edge, running most of the way round the edge of the pale green insole. The gap created under the insole is then filled – probably with cork as shown – along with a “shank” to stiffen the bit under the foot arch. The welt is then stitched to the sole, before the last is removed and we have a shoe, probably with all its components in place – ready for finishing.
There is another welting technique known as “Blake Sewn/stitched” or “Blake Welted”. It’s shown below – the stitching is done from inside the shoe and there is no separate welt. It is a simpler process to Goodyear welting and is sometimes combined with the cemented construction method.