438 



Ventilation of Poultry Houses. [oct., 



had any appreciable effect on any feature of the trees, nor on 

 the crops from them. The total effect did not amount to 5 per 

 cent, and even that effect was very doubtful. The only excep- 

 tion was in the case of nitrate applied in the early or late 

 summer, which in several seasons produced a good effect. 



In the tenth year (1904) the highly-manured plots showed an 

 excess of 3 per cent , and the deficiently-manured ones a deficit 

 of 8 per cent. By the addition of these figures to the nine 

 years' record, the average result for the ten years shows that 

 the highly-dressed plots gave a slight excess of '5 per cent, 

 over the nornal plots, and the under-dressed plots a deficiency 

 of 2 per cent. The most, however, that can be said from these 

 results is that the indications are in favour of the view that 

 manures are at last beginning to show their effect. If so, 

 during the next year or two it may be expected that this effect 

 will become more apparent. 



Experiments have been recently carried out at the South- 



Eastern Agricultural College, Wye, on the relative efficiency of 



poultry houses with and without ground 



Ventilation of ventilation. In previous investigations it 

 Poultry Houses. . J , " . -.u 



was found that m wooden houses, either 



resting on the ground or with floors and top ventilation, the air 

 changes about four times per hour, and in order to keep the air 

 pure each bird must have ten or more cubic feet of air space 

 allotted to it. In a wooden house slightly raised off the ground, 

 without a floor, the air was found to change about eight times 

 an hour, so that less cubic air space would suffice, but it was 

 thought that in this case the house must be draughty, and could 

 not fail to be injurious to the birds. 



In order to test the point two precisely similar houses were 

 used, one of which contained five hens and a cock and the other 

 ten hens and a cock. The birds were selected to be of as nearly 

 equal merit as possible, and the conditions were in other respects 

 identical. The house containing the smaller number of fowls 

 was provided with a floor and designated No. 6 ; the other 

 (No. 11) had its floor removed and was lifted three inches from 

 the ground, thus securing a current of air from below upwards. 



