RETTING 117 



clean, and clear, and artificially heated to an average 

 temperature of 22 C. (71:6 F.) and supplied to the retting 

 tanks as illustrated at Figs. 66 and 67 a plan and transverse 

 vertical section respectively. 



The letters distinguishing the various parts refer to corre- 

 sponding details in each diagram. A represents the " mill 

 race " in which the water from the river is temporarily stored 

 outside the retting room ; B is the wall of the building ; C, a 

 storage canal inside the building and running at the head of 

 all the retting vats. Cis provided with several steam pipes, D, 

 which rest at the bottom and run the full length of the canal. 

 The pipes, D, are continually charged with exhaust steam 

 received from the engines and boilers. E, E 1 , E 2 and E 3 

 represent the concrete walls of one tank, F. Each tank is 

 divided into two parts by the centrally -placed pillars, G. 

 A series of double gates, H and H 1 , run the full length of each 

 tank and are hinged to the wall, E, and the central pillars, G, 

 respectively ; likewise the gates, H 2 and H 3 , are hinged to the 

 pillars, G, and wall, E 3 , as shown in the plan. These gates are 

 free to pivot about their respective hinges from a horizontal 

 position when the tank is filled, and to an almost vertical 

 position when the tank is empty or requiring to be cleared of 

 its contents. 



Two water-tight sluice gates, J and J 1 , are provided for 

 each of the five tanks and are wide enough apart, when open, 

 to admit of the entrance of a small cart filled with flax straw, 

 whenever it is necessary to fill or empty the vats. K repre- 

 sents one of a series of upright rods with a cross plate at the 

 top for holding the gates, H, in a horizontal position during the 

 retting period. L represents valves between the mill race 

 and the warm water canal storage, M the valves between the 

 warm water storage and the vats, and N are valve plugs for 

 releasing any water as desired. 



The beets of flax, P, are placed in the tanks by hand, the 

 bottom row is almost vertical, but the second is more inclined 

 from the perpendicular. When the tank is filled with the 



