504 PRINCIPLES OF ANIMAL NUTRITION. 
kinds of work in order to eliminate so far as possible the influence 
of variations in external temperature and in the feeding, as well as 
to reduce the probable error of experiment. 
Work at A WaLk.—The experiments may be grouped into 
those in which the work was performed respectively at a walk and a 
trot. Those of the former category, being the more numerous, may 
be considered first. 
Work of Locomotion.—The following detailed comparison of the 
experiments of Period a upon rest and upon walking without load 
or draft will serve to further explain the method: 
REST EXPERIMENTS. PERIOD @. 
Ration, 6 Kg. Oats, 1 Kg. Straw, 6-7 Kg Hay. 
Per Kg Live Weight 
and. Minute: Respira- | Air Tem- | Relative Hours 
No. of Experiment. |---| __ tory perature | Velocity | Since Last. 
c Quotient. | Deg.C. | of Wind. | Feeding. 
Oxveeh ‘arbon 
yee Dioxide ¢ 
4.0, Oc. 
B10: goss none we es 3.94 3.81 0.968 | —5.0 0 3.0 
SOD), sisi BESS ES BE ES 3.92 4.02 1.025 | —0.5 1 2.5 
Ol ne § orient Maer 3 98 3.42 0.861 2.0 1 5.6 
BOM ois einata Sinue ts 4.06 4.04 0.997 5.3 3 2.0 
BA Oe oii ahr teksts 4.11 3 86 0.940 4.7 1 1.5 
DO Gloss casi gtigtecte tae 3.89 3.63 0.933 2.0 1 3.5 
AGG ates ee. aos oa eee 8 3.71 3.44 0.929 9.0 3 1.5 
Average ....... 3.94 3.75 0.950 2.5 1.4 2.8 
Corrected *..... 4.04 3.86 
In the same period eight experiments were made in which the 
-:ad-power was set as nearly horizontal as possible and driven by 
the steam-engine, the animal being simply required to maintain his 
place on the power. The results for oxygen were as shown in the 
first portion of the following table: 
* A comparison of Zuntz’s method with the results obtained in the Pet- 
tenkofer respiration apparatus showed that the gaseous exchange through 
the skin and intestines amounted to about 2} per cent. of the pulmonary 
respiration in case of the oxygen and 3 per cent in case of the carbon di- 
oxide. These additions are accordingly made to the figures of the respira- 
tion experiments and the results designated as “corrected,” 
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