THE RIPENING ROOMS OF RENNET CHEESES. 233 



ning of the year 1880, a method which he had devised of treating round 

 hard skim-milk cheeses. The unsatisfactory arrangement of cheese-cellars 

 not only increased the difficulty of treating the cheese in the store-room, 

 but also the whole manufacture of the cheese, inasmuch as it was necessary, 

 if it was wished to avoid serious mistakes, to take many precautions, in 

 the preparation of the cheeses in the cheese-rooms, against the harmful 

 influences to which they were subsequently exposed in the cheese-cellars. 

 At present, in the ripening-rooms of all the larger and better equipped 

 cheese factories, steam and warm- water heating apparatus are provided, as 

 well as apparatus for regulating the ventilation. Quite lately W. Helm, a 

 civil engineer, has attempted to perfect the arrangement of the ripening- 

 rooms for cheese manufacture. In the first place, according to him, it is 

 advisable to build the cheese-cellars either without windows, or to provide 

 them with very few and very small windows. The fewer windows present, 

 the more independent is one of the conditions of weather, and the easier it 

 is to maintain the temperature and relative moisture equable throughout 

 the whole year. Further, he would lead through the cheese-cellar, already 

 provided with a warm -water heating apparatus, a continuous stream 

 of air, saturated with water vapour, at a temperature of about 10 C., 

 before its entrance into the cellar, in a room specially constructed for this 

 purpose. The stream of air can be increased or diminished as desired. It 

 enters the cellar up above in the neighbourhood of the roof, passes 

 over the heating tubes, and is warmed by them, and by this warming 

 loses somewhat in its percentage of moisture. It travels through the 

 cellar, and finally leaves it by means of canals which have their exits near 

 the floor. By due regulation of the rapidity of the current of air and of 

 the heating, it is possible not merely to bring the temperature and the 

 moisture of the air to exactly the desired condition, but also to maintain it 

 equally at the desired temperature. Up till now only a few cheese-dairies 

 have been provided with this arrangement. Unfortunately it is somewhat 

 costly, and on this account it has not come into general use, while reliable 

 details in regard to its efficiency in working for a prolonged period, and 

 its technical and economic value, have not yet been furnished. Every im- 

 provement of the ripening-rooms for cheese manufacture must be regarded 

 as au advance in the interests of dairying. 



By the relative percentage of moisture of the air, is understood the 

 amount of the moisture, expressed in per cent, which the air under the 

 existing temperature and barometric pressure is able to absorb and become 

 saturated with. For example, a relative percentage of moisture of the air 

 of 75 per cent, would indicate that the air under the existing conditions of 

 temperature and air pressure only contains three-fourths of the water 

 vapour which would be required to bring it to the point of saturation. 



