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BRIALMON T — BRIARE to the air. The system is called top-fermentation, because the type of yeast employed develops on the surface of the liquid, forming the “ head.” The primary fermentation proceeds rapidly, and is usually complete in two to three days, and in the case of running ales the secondary fermentation is over within a fortnight, or even less. In the Continental bottom-fermentation system, the pitching and fermentation take place at a very low temperature (and in relatively small vessels), the cellars being maintained at a temperature of approximately 370-38° F. The yeast formed in the fermenting wort, the temperature of which rarely rises above 50° F., reposes at the bottom of the fermenting tun, and hence is derived the name of bottom-fermentation. After eleven or twelve days the primary fermentation is complete, and the beer is then run into store (lager) casks where it remains at a temperature approaching the freezing-point of water for six weeks to six months, or even more, according to the time of the year and the class of beer that is being brewed. To put the matter briefly, these are conditions eminently suitable for the employment of pure yeast and the maintenance of it in an uncontaminated state, whereas the high temperatures, the surface exposure of the yeast and so on, which are essential factors of the English system, tend to cause a rapid deterioration of the pure yeast originally used. It is also more or less generally held that there is no single type of yeast which will produce English beer with all its characteristics, but that the latter are due to the joint action of at least two or three varieties or species. It has been stated that satisfactory results have been obtained in English breweries by the use of mixed pure cultures, which fact is not without interest, inasmuch as it is a general rule that one type of yeast (and this applies to micro-organisms generally) tends to predominate in a given liquid at a certain temperature. Cases are known, it is true, where several micro-organisms are essential to the production of a certain substance. This form of multifold existence is termed “ symbiosis.” Thus for the process of fermentation which results in ginger beer, two organisms are necessary—the one a yeast, the other a mould. The process of lager beer brewing introduced by Messrs Allsopp into the United Kingdom exhibits many features of interest, as it combines infusion mashing with fermentation on decoction lines, and also embodies a new principle, that of vacuum fermentation, and many of the latest improvements in brewing technology. This process, which is used fairly widely in America, and has even taken a footing in Germany, is the Pfaudler vacuum fermentation process, of which the following is a brief description :— The wort is prepared on the ordinary infusion lines, and is then rapidly cooled by means of refrigerated brine before passing to a temporary store tank, which serves as a gauging vessel. From the latter the wort passes directly to the fermenting tuns, huge closed cylindrical vessels made of sheet-steel and coated with glass-enamel. Here the wort ferments under reduced pressure, the carbonic acid generated being removed by means of a vacuum pump, and the gas thus withdrawn is replaced by the introduction of cool sterilized air. The fermenting cellars are kept at a temperature of 40° F. all the year round, but the fermenting liquid, which shows 45° Fahr. at the commencement, gradually rises to a final temperature of about 53° F. The yeast employed is a pure culture bottom-yeast, but the withdrawal of the products of yeast metabolism and the constant supply of pure fresh air cause the fermentation to proceed far more rapidly than is the case with lager beer brewed on ordinary lines; it is, in fact, finished in about six days. Thereupon the air


supply is cut off, the green beer cooled by means of refrigerated brine to 40° F. and then conveyed by means of filtered air pressure to the store tanks. Here the secondary fermentation which takes three weeks proceeds at a low temperature (about 33° F.), but the gases of fermentation are now not removed, but, on the contrary, allowed to collect under pressure, so that the beer may be thoroughly charged with the carbonic acid necessary to give it condition, and in order to replace the gas withdrawn during the primary fermentation. When the secondary fermentation is completed (the attenuation being 68-70 per cent.) the beer is quite bright, but in order to make sure of its being perfectly free of yeast cells, &c., it is passed through a refrigerator and then through a filter, before going to the racking or bottling rooms, as the case may be. The beer is racked and bottled under counter pressure, so that none of the gas of the secondary fermentation can escape; indeed, from the time the wort leaves the copper to the moment when it is bottled in the shape of beer it does not come into contact with the outer air. (p. s.) Brialmont, Henri Alexis (1821 ), Belgian general and military engineer, son of General Laurent Mathieu Brialmont (d. 1885), was born at Yenloo in Limburg on 25th May 1821. Educated at the Brussels military school, he entered the army as sub-lieutenant of engineers in 1843, and was employed on the defences of Diest. From 1847 to 1850 he was private secretary to the war minister, General Chazal. In 1855 he entered the staff corps and rose to the rank of lieutenant-general in 1877, having been appointed, in 1875, inspector-general of fortifications and of the corps of engineers. The preparation and execution of the defence works of the country, and particularly of Antwerp, and of the new works of the Meuse were carried out under his direction. In 1883 he went to Rumania to advise as to the fortification works required for the defence of the country, and presided over the elaboration of the scheme by which Bucarest was proposed to be made a first-class fortress. On his return to Belgium in 1884 he resumed his command of the Antwerp military district. He retired in 1886, but continued to supervise the Rumanian defences. He is a member of the Belgian Royal Academy of Science, and is widely known as an expert in fortification and as a writer of many military works. He originated in 1850 Le journal de VArmee Beige. Some of his principal publications are : Considerations politiques et militaires sur la Belgique, 1851-52 ; Histoire du due de Wellington, 1856-57 ; Agrandissement general d’Anvers, 1858 ; Etudes sur la defense des etats et sur la fortification, 1863 • Traite de fortification-polygonale, 1869; La fortification a fosses secs, 1872; La defense des etats et les camps retranches, 1876 ; La fortification du champ de bataille, 1878 ; Tactique de combat des trois armes, 1881 ; Situation militaire de la Belgique: Travaux de defense de la Meuse, 1882; Le General Comte Todleben, sa vie et ses travaux, 1884; La fortification du temps present, 1885. 1 Brianza, a district of Italy, called the “ Garden of Lombardy.” It lies between the two southern arms of Lake Como, and stretches south as far as Mariano. It is a hilly and beautiful country, which, although possessing no large town, is densely populated, and, owing to the mildness of its climate and the softness of its air, is a favourite summer resort of the Milanese. Area, about 170 sq. miles. Briare, a town in the arrondissement of Gien, department of Loiret, France, on the right bank of the Loire, 43 miles in direct line S.E. of Orleans. A bust of Bapterosses (introducer of the button manufacture) was erected in 1897, and there is a handsome modern church. It has