Bologna construction is another Italian specialty; and on initial examination, it may look somewhat similar to Blake construction because of the row of stitching going from the inside of the shoe through to the outsole. However, the two construction methods really are very different. Bologna construction is sometimes called bag construction or tubular construction because the leather forming the upper goes all the way around the shoe, being sewn into a bag or a tube. The upper part of this leather is lined with normal lining leather. The lower part of this leather, where the foot will rest in the finished shoe, is lined with a soft leather insole much less stout than the kind of insole that you would find in a Goodyear or a Blake shoe. The upper lining is connected to the soft insole via a row of stitching on the underside of the both, so that you'll see a trench on the inside of a Bologna shoe. The row of stitching connecting the upper to the outsole is closer to the wall of the upper than it is on a Blake shoe, and its much less likely to come into contact with the wearer's toes.
As with Blake construction, one of the benefits of Bologna construction is that it's possible for the sole to be extremely close-cut, if that's aesthetically important. Bologna construction also makes for an extremely flexible shoe. Blake shoes are usually flexible, but they can't compare to the flexibility of Bologna shoes, all other things being equal, because of the thinness and pliability of the soft insole in Bologna shoes. The principal reason that Bologna construction exists is to produce extremely soft, slipper-comfortable shoes. That, of course, is one of the limitations of the construction method, too. Bologna constructed shoes aren't the most durable, and they don't provide the same degree of support to the foot while walking that Goodyear, Blake, or Blake/Rapid shoes do. Because Bologna construction has that row of stitching going from the inside of the shoe all the way through the outsole, Bologna shoes have the same moisture-wicking problem that Blake shoes do. And, for some reason, the outsoles of Bologna constructed shoes tend to be slightly convex, meaning that they wear more rapidly at the center of the sole than toward the edges.
The two most prominent practitioners of Bologna construction in Italy are A. Testoni and Artioli, although there are many other manufacturers who use it for at least some of their shoes. Gravati and Santoni both make excellent Bologna constructed shoes, and the diagram above was taken from the Santoni USA website.