Vacuum and Pressure Processes generally. Bréant’s. Bethell’s. Payne’s. Perin’s. Tissier’s. Vacuum by Condensation of Steam. Tissier. Bréant. Payne. Renard Perin, 1848. Brochard and Watteau, 1847. Separate Condenser. Tissier. Employ Sulphate of Copper in closed vessels. Bethell’s Patent, 11th July, 1838. Tissier, 22nd October, 1844. Molin’s Paper, 1853. Payen’s Pamphlet. Légé and Fleury’s Pamphlet. Current of Steam. Moll’s Patent, 19th January, 1835. Tissier’s ” 22nd October, 1844. Payne’s ” 14th Nov., 1846. Meyer d’Uslaw, 2nd January, 1851. Payen’s Pamphlet. Hot Solution. Tissier’s Patent, 22nd October, 1844. Knab’s Patent, 8th September, 1846. Most solutions used are heated. The following are the chief _ingredients_ which have been recommended, and some of them tried, to prevent the decomposition of timber, and the growth of fungi:-- Acid, Sulphuric. ” Vitriolic. ” of Tar. Carbonate of Potash. ” Soda. ” Barytes. Sulphate of Copper. ” Iron. ” Zinc. ” Lime. ” Magnesia. ” Barytes. ” Alumina. ” Soda. Salt, Neutral. Salt, Selenites. Oil, Vegetable. ” Animal. ” Mineral. Muriate of Soda. Marcosites, Mundic. ” Barytes. Nitrate of Potash. Animal Glue. ” Wax. Quick Lime. Resins of different kinds. Sublimate, Corrosive. Peat Moss. For the _non-professional_ reader we find we have _three_ facts: 1st. The most successful patentees have been Bethell and Burnett, in England; and Boucherie, in France: all B’s. 2nd. The most successful patents have been _knighted_. Payne’s patent was, we believe, used by Sirs R. Smirke and C. Barry; Kyan’s, by Sir R. Smirke; Burnett’s, by Sirs M. Peto, P. Roney, and H. Dryden; while Bethell’s patent can claim Sir I. Brunel, and many other knights. We believe Dr. Boucherie received the Legion of Honour in France. 3rd. There are only at the present time three timber-preserving works in London, and they are owned by Messrs. Bethell and Co., Sir F. Burnett and Co., and Messrs. Burt, Boulton, and Co.: all names commencing with the letter B. For the _professional_ reader we find we have _three hard_ facts: The most successful patents may be placed in three classes, and we give the key-note of their success. 1st. ONE MATERIAL AND ONE APPLICATION.--Creosote, Petroleum. _Order_--Ancient Egyptians, or Bethell’s, Burmese. 2nd. TWO MATERIALS AND ONE APPLICATION.--Chloride of zinc and water; sulphate of copper and water; corrosive sublimate and water. _Order_--Burnett, Boucherie, Kyan. 3rd. TWO MATERIALS AND TWO APPLICATIONS.--Sulphate of iron and water; afterwards sulphate of lime and water. Payne.