51. Fig. 13 shows the proper manner of dividing a main current into three branches so as to supply independent air flues. If the partitions A and B were absent, the greater part of the current would continue its motion until it was deflected by the side C. In that case, the flue D would receive a larger proportion of the current than either of the others, and the supply to the flue F would be quite insufficient.

A proper supply of air to each flue may be insured by adjusting the partitions A and B in such a manner that they will intercept the desired proportions of the main current before any change is made in its direction.

Fig. 13.

Fig. 14.

52. Fig. 14 illustrates the proper method of splitting up a main air-current into several smaller ones, and of subdividing these so as to supply a large number of vertical ducts. The method of proportioning the various branches so as to supply all the ducts with air at a uniform pressure, or otherwise, as desired, will be explained in a later section.