J. SPEIR. Influence of Temperature on Milk Yield. Experi- 

 ments in the Production of Milk in Winter under Free 

 " versus" Restricted ventilation. Trans. Highl. and Agr. 

 Soc. Scotl., XXI, 255-306. Edinburgh, 1909. 



Within the last few years it has been doubted in Scotland 

 whether the benefit to be obtained from keeping farm animals in 

 the comparatively high temperature aimed at in past years is really 

 as great as is generally believed. The prevalence of tuberculosis 

 among farm stock in most countries, and the success of the open 

 air treatment in arresting this disease among human beings, have 

 probably had something to do with the consideration which this 

 subject has received during recent years. 



But in most of the experiments carried out it has been generally 

 omitted to take into consideration the fact that where the heat 

 was derived from the bodies of the animals the air was much pol- 

 luted, and that the experiments, instead of being confined to one 

 essential viz., the degrees of temperature were in reality in- 

 fluenced by two viz., heat and fresh air. 



Most of the experimenters have, however, come to the con- 

 clusion that animals did not derive so much benefit from being 

 kept what was called warm as was generally supposed, neither did 

 they seem to suffer so much as usually expected when kept cool 

 or cold. 



Trials in America. In the winters of 1902-03 and 1903-04 the 

 Pennsylvania State College divided, each winter, 24 bullocks in 

 two lots, one of which was fed in a byre under a barn, and the 

 other in an open shed. The experiment in the latter year began 

 on loth Dec., and was continued till 4th April. During that period 

 the lot in the byre gained 230 Ib. on an average, while those in 

 the shed gained 227 Ib. For the first two months the average 

 temperature of the byre was 38.6 degrees F., while that of the 

 shed was 14.5 degr. F. The animals in the byre consumed rather 

 less food than those in the open, the value of the extra-food used 

 being equal to */ a d. per Ib. of live weight increase. In this expe- 

 riment, although carried on for two winters, the number of animals 

 employed was too limited to provide conclusive results and the 

 winter was too far advanced before the experiment began. 



Trials in England. In the autumns of 1901, 1902, 1903 and 

 1904 an interesting experiment having an important bearing on 

 this question was carried out at the Harper Adams Agricultural 



