A Study of Sterns

One of my favorite interpretations of the "Santa Maria" is the 1892 E.A. d'Albertis version. Unlike the other contemporary interpretations, it alone had a proper round tucked stern, with planking that ran up to the sternpost and round to the transom. There were problems with the design, of course, such its size and the sail plan. Still, it was superior to the Spanish Commission/Duro and Monleon versions.
However, in reviewing that design a little further, it became apparent that it has much in common with two other, more recent, designs; the Serrano version from the early 1990's, and Vazquez/Coin-Cuenca version from 2012. The similarity lies in the stern.

All three designs have planking that has very smooth runs, ending at the rudder. This design produces hollow stern lines that would definitely enhance sailing. It was for this reason that Vazquez and Coin-Cuenca chose the design, as a way to explain the "Santa Maria's" ability to haul close to the wind. However, all three designs borrow heavily from one source, "Instruccion Nautica" by Garcia del Palacio. This work, an early shipbuilding treatise, was published in 1587, ninety five years after Columbus' first voyage. As such, it is a questionable choice for a reference. However, it is really the only treatise from any time near 1492 that covers the shape of ships.

A large nao from "Instruccion  Nautica"

A smaller ship from "Instruccion Nautica"

Before we go any further in this discussion, let's review how the sterns of ships changed in Europe. The first real leap occurred in northern Europe with the development of the stern rudder, which was epitomized by one of the most successful Medieval ship designs, the "cog". This single square sail rigged cargo vessel first began to appear in the 13th century, and soon was plying the coasts of Europe, eventually reaching the Mediterranean. It was shell built, using clinker construction for the most part (the Bremen cog used a form of carvel construction on the lower hull). This form of construction also produced very hollow runs both fore and aft.
Meanwhile, the ships of the Mediterranean were smooth carvel built, usually rigged with triangular lateen sails, and used twin steerboards for rudders. Their hulls were round tuck, with the planks ending at the stem and stern. This design would persist even into the 15th century, and possibly beyond.
By the 15th century, we begin the see a synthesis of the two designs; the northern single rudder design on carvel built hulls. This is exemplified by the famous Mataro nao model. The design retains the Mediterranean/southern European carvel hull, with the planks against one another instead of overlapping in the lapstrake clinker fashion of the north. One interesting feature, though, is the extended sternpost, that almost looks like an after thought but was clearly an attempt to adopt the southern style hull to a straight single rudder. It was a compromise that we will look at more closely shortly.
The ultimate form of large carvel hull can be found in the Portuguese carrack "Santa Catarina do Monte Sinai" from the first quarter of the 16th century. In this design, however, it is not clear if the planking runs to the sternpost, or if a rounder and a deeper sternpost is being used.

Now, let's return to the earlier stern design that became prevalent on carvel built ships, the design that used the deeper sternpost like found on the Mataro model. In the artwork of Vittore Carpaccio's "Saint Ursula Cycle", a number of ships appear. These are done in excellent detail, and on one painting, the sterns can be seen, and indeed are this design. These date from the 1490's.

Detail from "The Meeting of Ursula and the Prince"

This design is borne out in some additional artwork from the period as well. In the woodcuts found in Breydenbach's "Peregrinatio in Terram Sanctam", the artist Erhard Reuwich, who accompanied Breydenbach on his journey in 1483-84. On the journey, the pilgrims stayed in Venice, which Reuwich illustrated as having a number of ships apparently fitting out. One of these is seen from the starboard, and again shows what appears to be that very round stern.

The Flemish master known variously as "W.A.", or "Master W with the Key" also illustrated this same design, which by that point had started to show up in northern Europe.

But, all is not as clear as it seems. W.A. also did an illustration of a large ship that is not particularly clear as to how the planking ran astern.

Then, in another woodcut found in "Peregrinatio" we find a large carrack viewed astern, and it is not clear where the planking ends as well.

We could again reference the large Portuguese carrack "Santa Catarina", but not only is the painting slightly dubious, it really falls into a later period, and therefore quite possibly out of the question in discussions about late 15th century Iberian ship design. 

Five carracks, all apparently the "Santa Catarina". Attributed to Joachim Patinir

There is still the possibility that the Santa Catarina is of some utility in this discussion. Obviously, it had to have evolved from earlier designs. Most maritime historians believe that the caravel had square sterns in the late 15th century, and as a result clean runs of planking to the sternpost. It is possible that the Santa Catarina painting shows the end result of this, just before the shift to square sterns on larger vessels.
All of this is speculation, of course. While it would be easy to dismiss those three Santa Maria designs that opened this topic as too modern in hull design, we know that sharp runs were possible in both the earlier northern shell-built clinker design and in the contemporary square sterned caravels. In the end, at best the evidence is inconclusive.
Still, and I readily admit this, I am a fan of d'Albertis' work. Perhaps all that design needs is some rehabilitation, as well as a bit of size reduction. It really was the best design from those initial attempts to distill the appearance of Columbus' flagship.