THE CALORIMETER SYSTEM AND MEASUREMENT OP HEAT. 163 



Before weighing the absorbing system, it is necessary that the subject 

 draw off all drip water that can be removed from the cans at the corners 

 of the absorbing system. It is absolutely essential that no considerable 

 amount of water remains in the aluminum shield. It occasionally 

 happens that the outlet pipe from the shield becomes clogged with dirt 

 or dust, and the drip water, instead of running directly into the cans, 

 accumulates in the shield itself. Under these conditions, when the 

 subject attempts to adjust the absorbing system for weighing, the water 

 will flow back and forth from one end of the absorber to the other end 

 and thus produce a constantly changing weight that can not be properly 

 estimated. 



After the weighing is completed, the observer outside raises the lever- 

 arm until the flexible cable begins to raise the shields, thus removing a 

 portion of the weight of the absorbing system. The lead counterpoises 

 then settle into position and the subject can remove the pipes used to 

 suspend the absorbing system. After removing the cross, the rubber 

 stopper can be re-inserted in the fiber tube. 



Routine of the weighings. Since the experimental day begins at 7 

 o'clock in the morning, it is desirable to have the weight of the sub- 

 ject, bedding, and furniture at this hour every day ; consequently the 

 following routine was utilized in the later experiments of 1904 : The 

 subject was called at 7 a. m. He immediately rose, and, having slept in 

 underclothing and socks, no change in clothing was made. He then 

 rolled up the bedding, fastened the bed to the side of the wall, sus- 

 pended the chair in which he was to be weighed from the iron hook in 

 the end of the suspension rod, and, taking all the bedding and clothing 

 in his lap, sat in the chair. By means of a speaking tube and an electric 

 bell connected with the closet upstairs in which the balance is placed, a 

 signal was given, whereupon two observers upstairs brought the balance 

 to equilibrium and the actual weight was recorded by both. The subject 

 was then signaled to get up from the chair, and he immediately placed 

 all the clothing (save that which he was actually wearing) and the 

 bedding in the chair. This weighing was made, followed by the adjust- 

 ment and weighing of the absorbing system. 



It is thus seen that the most rapidly fluctuating weight, i. e., the 

 weight of the man, was made first, almost immediately after 7 o'clock. 

 The weight next most liable to fluctuate, i. e., that of the bedding and 

 of the clothing, was made a few moments later, and the absorbing system, 

 which it is supposed would fluctuate in weight the least, especially at 

 this hour of the day, was not weighed until the last. 



The necessity for weighing the man as soon as possible after 7 o'clock 

 is seen when it is considered that there is a loss in respiration and per- 



