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The cannon was recovered from the sea in the port of Stari Grad (Fig. 1). It was pulled ashore to the locality of Podlaže, loaded into a van and transported, under specialist supervision, to the Conversation-Restoration Department of the Arts Academy in Split.

The restoration treatment began with the removal of the thick incrustation made of organic growth (various species of shells, crayfish and other sea organisms) which accumulated on its surface over the years. The cleaning was done mechanically (Fig. 2).

Cannons of this type are commonly made of cast iron which deteriorates fast. Also, because of its prolonged exposure to salt water, the cannon needed desalination. The desalination treatment was  carried out twice, before and after electrolysis. The first desalination treatment started on April 1, 2008, and lasted for a week. After that, we had a better grasp of its state of preservation. It turned out that the sea salt had damaged its surface, speeding up corrosion. In some very badly corroded parts the damage was so extensive that we had no other choice but to wash away the crumbling bits of iron with water lances. In order to stabilize the damaged surfaces (and the rest of the cannon) we used electrolysis. Electrolysis is a chemical process which, with the help of current, triggers oxide reactions on electrodes. We used sodium carbonate as electrolyte. The electrolysis started on  April 4, 2008 and ended on April 22, 2008. After this, we returned the cannon into the desalination pool (which we filled with clean water) to complete the desalination process (April  29, 2008). In the end, the cannon was washed thoroughly with a high pressure water lance (Fig. 3). This had to be done in order to remove the new dirt which had built up during the desalination process.

After the cannon was rinsed, the surface was polished with the electric grinder and a metal brush with which the most stubborn accretions were removed.  Although the corrosive oxides affected the appearance of the cannon only slightly, they could speed up the surface corrosion, and since it was not possible to remove all oxides with the grinder, we passed to  sandblasting. The surface of the cannon was sandblasted with quartz sand. In this way iron oxides were removed completely (Fig. 4).

When sandblasting was finished, we cleaned the barrel tube. As it could not be simply washed, we had to use a drill so that sludge and solid dirt which had accumulated in the barrel would break up and disintegrate (Fig. 5). After that we could wash away the dirt, using the water lance. Upon the completion of the cleaning, it was necessary to protect all the surface of the cannon with an appropriate metal paint. Before that we had to ensure that there was no water left on the surface or in the barrel. It was impossible to eliminate moisture altogether, but we could reduce its amount to the minimum. This was done by heating the surface with a burner and by allowing it to dry slowly.

We selected a led containing primer which would  protect the cannon from humidity and rainwater, as it was to be displayed out of doors. We applied three layers of primer. For the final (top) coating we used a nitrogen-based black paint not solely for aesthetic effect, but also because of its anticorrosive properties. It was applied in three layers (Fig. 6). The barrel was protected with a coat of paraffin and wax.

Since the cannon was found in a rather poor condition, we had to monitor closely its behavior in the new environment. Unfortunately, our secret fears were confirmed after a while, when new rust appeared on the surface. To eliminate it we had to remove the top layer of black paint, which was carried out by sandblasting. After the paint was removed, we had to warm up the surface again, in order to release moisture which appeared during the new cleaning. We continued warming it up, because this time we decided to treat it, like the barrel, with paraffin and wax. The warm wax fills the holes much easier and the surface gets coated evenly. The process was repeated several times. In this way the surface was protected from any external influence.

After the restoration of the cannon was completed, we had to build a mount. As a model, we chose  the wooden mount of the similar cannon placed in front of the Maritime Museum in Split. After several tests we decided to paint it in walnut colour, with matt paint. The paint was applied in one thick layer. After this the mount was varnished with two layers of varnish, by means of which we additionally protected wood and intensified the colour. When the varnish dried up, a thin layer of wax was applied for further protection of the wood and intensity of colour (Fig. 7).