1 68 A RESPIRATION CALORIMETER. 



if positive, on the right-hand side of their respective columns, under the 

 sign +, and if negative, on the left-hand side, under the sign . As 

 has been explained, the deflections should with each key be as near 

 zero as possible. This is especially necessary with Nos. i and 2. At the 

 end of each hour the sum of the readings in each of these columns is 

 taken, and the difference between the sums carried over to the following 

 sheet, to be compensated for if possible during the next hour. 



The fifth column is headed "Inside temp., No. 5." In this are 

 recorded the deflections with key No. 5, which represent the temper- 

 ature just inside the copper walls as measured by the electrical ther- 

 mometer described on page 135. This temperature is held as nearly 

 uniform as practicable. 



The three columns following are used for recording the temperature 

 of the incoming and outgoing water current. That headed ' ' Temp, 

 water therm. ' ' gives the readings of the mercurial thermometers, that in 

 the outgoing water current being recorded above with the correspond- 

 ing reading of the incoming water current immediately below. In the 

 next column are the readings as corrected for the calibrations of the 

 thermometers (see p. 133). The column headed ' ' Difference ' ' contains 

 the differences between the corrected readings for the incoming and 

 outgoing water current, or, in other words, the rise in temperature of 

 the water current. 



In the column headed " Heat calculations " are recorded various mis- 

 cellaneous data. The left-hand margin contains the readings with 

 key No. 7, the electrical thermometer connected with the copper walls 

 and showing their temperature. Readings of T, the mercurial ther- 

 mometer just outside the window, and of B, the mercurial thermometer 

 inside (see p. 120), are also taken from time to time and recorded in 

 this column. Whenever one of the cans on the water-meter is full, the 

 reading of the dial, together with the time, expressed in hours, minutes, 

 and seconds, is recorded ; for example, 79.8 at 10 o'clock 52 minutes 

 38 seconds. Just below this is written the sum of all temperature dif- 

 ferences while the can was filling. This sum divided by the number 

 of readings gives the average rise in temperature of the water in the 

 can. For example, the sum of n readings was 49.02, the average of 

 which was 4.456. This value, multiplied by the weight of the water 

 as determined from a plotted curve for the point corresponding to the 

 figure registered by the dial (see p. 132), gives the heat in calories 

 brought out from the calorimeter system for the period of time. This 

 value is recorded in the last column (45.01 calories). 



The final column, marked "Sundries," also serves for miscel- 

 laneous data. When the rectal thermometer is in use, its readings 



