Criteria of Intervention on the fortiďŹ cations and the city of Valletta
Image 17. Located by C Borg Works Archives, Floriana.
234
buzzing with activity. Today it is an important route through which tourist arriving from the cruise liners enter Valletta. The project also envisaged the need to rehabilitate all the area, with the introduction of new wider pavements together with the creation of a public piazza (the original site of the fish market), hence giving the much needed new life to this important street and Place. The documentation exercise was followed by a detailed survey with the aim of establishing the state of conservation of the various elements making up the gate. Victoria Gate was found to be structurally sound but presented a highly compromised surface with considerable accumulations of black crust and heavily eroded sculptural details. Black crust is composed of carbonaceous deposits made up of small chemical particles, similar to carbon, derived from different sources including internal combustion engines. These deposits tend to accumulate over areas that are not subject to rain washing. Perhaps not surprisingly the greatest accumulations of black crust were present on the vaults of the tunnels behind the façade which for years have functioned as one of the main traffic routes in and out of Valletta. The surge in the use of cars, and their concentration in the Valletta/Floriana area, has contributed to the decay of the monument in more than one sense. Primerally cars functioned as vehicles for the transport of noxious substances which where emitted directly underneath the gate and become tenaciously attached to it surface. This car induced decay had also
a more subtle aspect to it. In the late 1970s the whole urban set-up of the area was re-thought with the car as its main focus. This led to a drastic alteration of the area with the creation of the Valletta ring-road which rendered the route passing through marina street and Victoria gate noting more that an appendix to this road. This lose of status and context where major contributes to the decay that characterised the area for the past three decades. Furthermore, its location within the Grand Harbour area means that Victoria Gate stood in a most polluted environment. The harbour area represented, for many years, the industrial heart of Malta accommodating coal-burning ships and first the Floriana, and later the Marsa, power stations. In addition to this, the monument has also been subjected to the deteriorating effects of marine elements the most damaging of which is sodium chloride (marine salt). This was most evident in the deteriorated sculptural details. The physical characteristics of the globigerina limestone out of which these are made makes them susceptible to salt-induced deterioration. Furthermore their location in the upper part of the monument means that they are exposed to daily cycles of wetting and drying which are accelerated by the action of the wind and sun. This means that the rhythm of the process of salt dissolution and re-crystallisation, governed by the rate of water evaporation, is very sustained and led to accelerated decay. The project entailed the rigorous conservation and restoration of the gate’s masonry and the vaults. The precarious state of part of the masonry entailed the use of the most delicate procedures so the restorers have opted for cleaning with the use of hand brushes and poultices. The poultices that were used was a paper pulp which was wetted with clean water. The poutice was applied to the stone surface and left to act for a predetermined period of time. Its malleable nature, similar to a paste, means that it can be applied without much difficulty even to drastically uneven surfaces such as sculptured elements. The material applied has such properties that will maintain a localised high degree of humidity that will act on the surface encrustations of a particular area rendering them less tenaciously attached and subsequently absorbing them onto its own surface. Thus when the poultice is removed part of the underlying encrustation is also removed. These results are obtained without any mechanical action on the surface.