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stables no provision is made for admitting fresh air, 

 or for drawing off that which has become charged 

 with impurities and robbed of its life-giving oxygen. 

 Without doubt the alarming prevalence of tubercu- 

 losis among cattle is largely due to this neglect. 



Plan for a Ventilated Barn. This neglected feature 

 of barn construction is deemed worthy of special men- 

 tion in this book. On the following pages will be 

 found detail plans for a barn provided with an ade- 

 quate system of ventilation. 



A Cross section, through feed chutes and venti- 

 lating shafts, of the barn shown on preceding page. 

 B Cross section of the same barn, through ventilat- 

 ing shafts, placed at the ends, on either side of the 

 double doors. This method will, doubtless, be pre- 

 ferred by some farmers, as it will allow of keeping 

 feed chutes filled with hay, sufficient for several feed- 

 ings. However, it is not a wise plan to leave hay 

 thrown down in the stables, as it will absorb the im- 

 pure air and bad odors of the barn. In both cases feed 

 chutes must be kept closed, in order to insure proper 

 draft to ventilating shafts. C Vertical section 

 through floor, feed chute and ventilating shaft, show- 

 ing trap door closed to insure proper circulation of 

 air. D Same, showing trap door open for feeding. 

 E Cross section of same at the second floor. Size 

 of chute, 3x3^ feet. Size of ventilating shaft, 

 1/2x3^ feet. F Section through wall and window, 

 showing sheetiron wind-shield, thrown back, and 



