REPORT OF MR NELSON L. DERBY.
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fire had taken place, and should have passed by had it not been for the crowd assembled in the vicinity.
Having called attention to the activity in building, reigning at present in Vienna, and referred to the especial efforts made to beautify the city ; and also given some hints as to the substantial character of the work done, I wish now to discuss these matters more at length. The field here is an especially good one for study, from the fact that so many of the buildings erecting are to be of a monumental character, where lio expense or pains are spared to secure durability and preservation from the dangers of fire. The German race is not an inventive one, but is certainly acquisitive. There is little new and good that other nationalities contrive that they do not sooner or later apply to their own purposes;—thus, all the methods of construction through the use of iron as devised by the French, are, perhaps, to-day more widely used in Vienna than in Paris. A work has been published by a North German, Brandt, upon this subject, and is filled with the most useful drawings made by himself in Paris, London and Berlin, of all varieties of construction in this material. Many of these are, without doubt, known in America, but not as widely as they should be, and this work is well worthy of translation into English and publication at home. The first matter to be looked into would appear to be that of mastic, from its predominant use and excellent character in this city. Unfortunately, no books have been written upon the subject, and what information I have been able to collect upon it has been gained by questioning builders and masons, and in some cases architects, though these latter seem in general to know less of the matter. Whatever the nature of the material may be, it is always desirable to give it a firm hold upon the fronts to which it is applied, and this is here gained by the use of soft, porous bricks, laid with joints open to a depth of an inch from their external surface, and from half an inch to an inch in width. This has been stated above already, but I repeat it here as of particular importance. The mastic keys itself into these crevices exactly as the plaster of a wall or ceiling is held in place by the openings between the laths. The material used in Vienna is of several varieties, but the chief heads under which it can be classified are two : that prepared