Another series of experiments was carried out with Mr. L.E. Emmes, who has also long been associated with this laboratory. This series extended from April 26, 1909, to July 29, 1915, inclusive, all but one of the experiments being made prior to June 6, 1911. Data for 8 half-hour periods, secured approximately between 8 a. m. and llh30m a. m., are available for comparison purposes.

1Benedict and Higgins, Am. Journ. Physiol., 1912, 30, p. 217.

Considering first the table showing the carbon-dioxide production (table 39), it is found that with this subject the average value for the first period is extraordinarily high (224 c.c), while the subsequent values all lie very close to 200 c.c. If we exclude the first period, we find no evidence of change in the value as the day progresses. A closer examination of the figures shows that the high value on the first day is determined, in part at least, by values on May 3 and 7, on which the carbon dioxide excreted was 252 c.c. and 246 c.c, respectively, both values being considerably higher than those found on the subsequent periods of the same day. The average carbon-dioxide production of this subject over a period of approximately six years was 204 c.c. An examination of the figures in the extreme right-hand column shows a tendency for the carbon-dioxide production to be lower during the last half of the series than during the first half.

Table 39. - Carbon Dioxide Produced At Different Times Of Day In Respiration Experiments; Subject L. E. E., In Post-Absorptive Condition And Lying On Couch

(Values per minute).

Average age, 31 years. Average body-weight (naked), 59.8 kilograms. Height, 176 cm.

Date.

Duration of experiments.

First half hour.1

Second half hour.1

Third half hour.1

Fourth half hour.1

Fifth half hour.1

Sixth half hour.1

Seventh half hour.1

Eighth half hour.1

Average.

1909.

c.c.

c.c.

c.c.

c.c.

c.c.

c.c.

c.c.

c.c.

c.c.

Apr. 26

8h09ma.m. to 9h37ma.m. .

225

200

212

210

....

212

Apr. 28

8 10 a.m. to 9 15 a.m. .

222

203

211

..

...

..

212

Apr. 30

8 03 a.m. to 9 08 a.m. .

211

193

203

■ • •

• ■ ■

...

202

May 3

8 03 a.m. to 9 15 a.m. .

252

217

231

...

..

233

May 7

8 06 a.m. to 9 12 a.m..

246

218

217

...

...

..

227

May 10

8 32 a.m. to 11 02 a.m. .

196

191

191

204

..

196

May 13

8 12 a.m. to 10 47 a.m. .

200

207

209

206

209

210

...

..

207

May 20

8 20 a.m. to 10 44 a.m. .

234

228

224

216

233

233

...

228

May 22

8 40 a.m. to 11 16 a.m. .

230

221

228

238

249

248

...

236

June 1

8 43 a.m. to 10 56 a.m..

215

208

218

204

212

230

....

215

June 9

8 58 a.m. to 11 13 a.m. .

219

201

210

228

219

215

June 16

8 29 a.m. to 10 46 a.m. .

204

198

211

218

217

...

...

210

1910.

Feb. 4

8 32 a.m. to 11 42 a.m. .

205

204

203

187

211

201

197

201

Feb. 8

8 38 a.m. to 11 30 a.m..

197

195

197

199

187

197

195

Mar. 7

8 47 a.m. to 11 52 a.m..

• • ■

206

194

199

189

205

190

197

Mar. 19

8 44 a.m. to 11 45 a.m. .

206

192

199

208

197

209

207

203

Mar. 29

8 29 a.m. to 11 40 a.m. .

216

178

197

178

195

178

205

192

June 7

8 32 a.m. to 11 45 a.m. .

199

199

182

194

. .

198

194

June 11

8 44 a.m. to 11 27 a.m. .

• . •

202

195

199

195

208

198

200

July 1

8 47 a.m. to 10 56 a.m. .

193

193

199

196

. .

195

July 6

8 36 a.m. to 11 10 a.m. .

202

194

215

194

222

205

...

205

July 14

8 40 a.m. to 11 20 a.m..

188

191

191

186

191

201

191

Nov. 26

8 25 a.m. to 10 20 a.m. .

220

220

222

225

222

Nov. 29

9 15 a.m. to 10 59 a.m. .

. . >

200

207

211

205

..

206

Dec. 3

8 24 a.m. to 9 39 a.m. .

196

194

201

. .

197

Dec. 9

7 59 a.m. to 8 44 a.m. .

205

192

...

199

1911.

Mar. 23

8 42 a.m. to 9 46 a.m. .

202

202

209

...

204

May 15

8 44 a.m. to 9 53 a.m. .

189

189

188

189

May 22

8 37 a.m. to 9 44 a.m. .

184

198

187

. .

190

May 29

8 30 a.m. to 10 24 a.m. .

185

182

178

187

...

..

183

June 5

8 48 a.m. to 10 02 a.m. .

. ■ .

187

180

201

..

189

1915.

July 29

8 30 a.m. to 12 55 p.m. .

194

183

189

Days..................

8

24

30

26

20

18

12

7

232

Minimum.............

200

184

178

178

178

186

178

190

183

Maximum.............

252

230

231

228

238

249

248

207

236

Average................

224

204

202

200

204

208

208

199

204

M. V...................

14.9

9.9

10.8

10.3

11.8

13.9

12.3

4.1

10.8

1The experimental periods were usually 15 minutes in length and in most instances there was but one period in the half hour. 2The total number of periods in which the carbon-dixoide was determined in the 32 experiments was 148.

Table 40. - Oxygen Consumed At Different Times Of Day In Respiration Experiments; Subject L. E. E., In Post-Absorptive Condition And Lying On Couch

(Values per minute).

Average age, 31 years. Average body-weight (naked), 59.8 kilograms. Height, 176 cm.

Date.

Duration of experiments.

First half hour.1

Second half hour.1

Third half hour.1

Fourth half hour.1

Fifth half hour.1

Sixth half hour.1

Seventh half hour.1

Eighth half hour.1

Average.

1909.

C.C.

c.c.

c.c.

C.C.

c.c.

c.c.

C.C.

c.c.

c.c.

Apr. 26

8h09ma.m. to 9h37ma.m..

242

243

244

239

242

Apr. 28

8 10 a.m. to 9 15 a.m. .

236

233

236

...

235

Apr. 30

8 03 a.m. to 9 08 a.m. .

234

239

248

...

240

May 3

8 03 a.m. to 9 15 a.m. .

229

236

232

...

232

May 7

8 06 a.m. to 9 12 a.m. .

243

232

232

...

236

May 10

8 32 a.m. to 11 02 a.m. .

...

...

242

235

231

243

238

May 13

8 12 a.m. to 10 47 a.m..

238

246

239

252

235

232

240

May 20

8 20 a.m. to 10 44 a.m. .

241

257

256

249

252

244

250

May 22

8 40 a.m. to 11 16 a.m. .

240

252

249

253

263

253

252

June 1

8 43 a.m. to 10 56 a.m. .

268

248

277

252

273

271

265

June 9

8 58 a.m. to 11 13 a.m..

...

248

247

258

260

274

257

June 16

8 29 a.m. to 10 46 a.m. .

263

280

264

257

264

266

1910.

Feb. 4

8 32 a.m. to 11 42 a.m..

232

239

248

238

...

259

273

248

Feb. 8

8 38 a.m. to 11 30 a.m...

253

235

247

249

247

243

...

246

Mar. 7

8 47 a.m. to 11 52 a.m. .

■ > ■

238

238

245

...

270

...

248

Mar. 19

8 44 a.m. to 11 45 a.m. .

248

236

244

253

252

236

...

245

Mar. 29

8 29 a.m. to 11 40 a.m. .

249

235

244

237

238

254

243

June 7

8 32 a.m. to 11 45 a.m. .

244

235

225

...

230

241

249

237

June 11

8 44 a.m. to 11 27 a.m. .

• • •

...

234

238

233

241

244

238

July 1

8 47 a.m. to 10 56 a.m..

■ . •

248

233

242

240

241

July 6

8 36 a.m. to 11 10 a.m. .

232

231

234

237

259

262

243

July 14

8 40 a.m. to 11 20 a.m..

...

233

231

232

232

235

244

235

Nov. 26

8 25 a.m. to 10 20 a.m. .

257

248

256

263

256

Nov. 29

9 15 a.m. to 10 59 a.m. .

. . ■

271

261

272

274

270

Dec. 3

8 24 a.m. to 9 39 a.m..

237

233

237

...

* . .

...

236

Dec. 9

7 59 a.m. to 8 44 a.m. .

251

250

251

1911.

Mar. 23

8 42 a.m. to 9 46 a.m..

235

234

240

...

...

236

May 15

8 44 a.m. to 9 53 a.m..

251

241

238

...

...

...

243

May 22

8 37 a.m. to 9 44 a.m. .

254

242

248

...

...

248

May 29

8 33 a.m. to 10 24 a.m..

225

235

243

242

...

236

June 5

8 48 a.m. to 10 02 a.m. .

■ . ■

237

223

226

229

1915.

July 29

8 30 a.m. to 12 55 p.m..

229

224

227

Days ..........

8

24

29

26

20

16

12

5

232

Minimum ............

229

225

224

223

226

230

235

244

227

Maximum.....

251

268

280

277

263

273

274

273

270

Average ...............

239

244

241

244

245

249

255

253

244

M. V.................

5.0

9.5

7.5

9.5

9.5

12.6

13.4

8.6

8.1

1The experimental periods were usually 15 minutes in length and in most instances there was but on period in the half hour. 2The total number of periods in which the oxygen was determined in the 32 experiments was 143.

When the values for the oxygen consumption given in table 40 are examined, it is seen that the discrepancy in the carbon-dioxide production which was noted for the first period does not appear in the oxygen values. Indeed, there is a possible tendency for the oxygen consumption to increase slightly as the day goes on. The average value for the first half-hour drawn from 8 periods is 239 c.c.; those for the fifth to the eighth periods are all 245 c.c. or over, with the last three perceptibly higher. On the other hand, the average value for the whole series of observations is 244 c.c, which does not indicate a trend toward variation in oxygen consumption as the day progresses. As was the case with H. L. H., variations from period to period on the same day are frequently noted.

The mean variation, like that for the carbon-dioxide production, is small, which is indicative of a satisfactory technique. The values in the extreme right-hand column show that in a period of six years there was no apparent tendency for the oxygen to alter its value to any great extent, but as the last three values are measurably lower than the average, it may be necessary to limit the period of approximately constant metabolism to the time between April 26, 1909, and May 22, 1911, especially as but one value was obtained after June 5,1911. The data in table 40 give no conclusive evidence, however, that a period of six years is sufficient to alter materially the average metabolism of this subject.