TABLE 52.-Number and yearly output of commercial bituminous-coal mines, by

size classes, 1905–1923

. This table shows mines, not companies, and should not be confused with other tables that include country banks and many wagon mines shipping by rail,

RELATIVE NUMBER OF IDLE, PART-TIME, AND FULL-TIME MINES

Not only does the number of mines in operation vary from year to year, but within the limits of a single year varying conditions of the market may be reflected in changes in the number of active mines. A significant index of this variation is afforded by Table 53, which shows the proportion of idle, part-time, and full-time mines in the group that reported their weekly running time to the Geological Survey in the three years 1921–1923. These mines, number

FIGURE 43.--Number of commercial mines in each size class, 1905–1923. Note that wagon mines are not

included

ing about 2,500, are of course only a small part of the total number of mines, but they produce more than half the total output. They include no wagon mines. They are commercial operations of some size, each affiliated with an operators' association or large enough to maintain a permanent office force and to send in a report weekly to the Survey. They may be taken as fairly representative of the commercial mines exclusive of the consumer-owned tonnage.

Table 53 is based on a special recompilation of the Geological Survey's records by the Bureau of Labor Statistics. The data are shown graphically in Figure 29.

Number Per cent Number Per cent Number Per cent Number Per cent Number Per cent Number Per cent Number Per cent Number Per cent

122

10.4
7.5
6.9
7. 2
6.5
7.9
7.3
7.1
7.4
7. 6
7. 4
7.5
7.6
8. 8
7. 3

11.8
10.6

529

6.9

Dec. 9. 2, 178 131 6.0 204 9.4 602

27.6 Dec. 16.

426 2,091 92 4.4 245

11. 7

606 Dec. 23

29.0 2, 104

480 81 3.8 236

11.2

706 Dec. 30.

33. 6 2, 228 106 4.7

427 195 8.7 652

29.3

561
1923
Jan. 6.

2, 442 128 5.2 205 8.4 657
Jan. 13.

26. 9 598 2, 428

5. O 239

9.8 Jan. 20.

718 29. 6 565 2, 412 116 Jan. 27.

4.7 266 10.9 747 30.6 687 385

93 3. 9 248 Feb. 3

10.4

794 33. 3 559 2, 468 146 5.9 233 Feb. 10.

9.4

797 32. 3 595 481 152 6.1 218 8.8

740 29. 8
Feb. 17

571
2, 513
212 8.4 281 11. 2 757

30.1
Feb. 24.

511 2, 411

221 9. 2 285 11.8 732 Mar. 3.

30.4 611 2, 438 199 8.2 288

706 28.9
Mar. 10

489
2, 413 202 8.4

255
Mar. 17

695 28.8
2, 434 252 10.4

215 8.8 676 Mar. 24.

27.8 550 2,274 239 10.5

158

631 27.8
Mar. 31

496
2, 341 275 11. 7 184 7.9 610 26.1 571
Apr. 7

355 356 15.1 155 6.6 571 24. 3 558
Apr. 14.
342 407 17.4 156 6. 7 608

25. 9

491
Apr. 21.

2, 363
439 18. 6

118

5. O 511 21. 6 539 Apr. 28

2, 355 520 22. 1

4. 3 505 21.5 516 May 5.

2, 363 529 22.4 107

4. 5

495 21.0 545 May 12. 2, 372 533 22.5

81 3.4
436 18. 4

560
May 19
2, 416 543 22. 5

94 3.9 474 19.6 510
May 26
2, 371 529 22.3

69 2.9 335 14.1 484 June 2

2, 277 511 22. 4

64 2. 8 343 15.1 504 June 9.

2, 293 503 21. 9

69

3. O 274 12. 0 505 June 16 2, 287 520 22. 8

56 2. 4 338 14.8 468 June 23. 2, 620 730 27.9

89 3. 4 382

14.6 453 June 30 541 741 29. 2 101

4.0 396 15.5 410 July 7

2, 499 797 31.9

87 3. 5 363

14.5

407
July 14
2, 390 729 30.5

88 3. 7 216 9.0 324
July 21.

2, 476 729 29.4

57 2.3

213 8.6 355 July 28. 2, 608 741 28.4

72 2. 7

247 9. 5 462 Aug. 4. 2,584 723 28.0

77 3.0 280

10.8 418 Aug. 11 2,517 721 28. 6

87 3. 5

300 11. 9 380 Aug. 18 2, 219 632 28. 5

41 1.8 199 9.0 Aug. 25. 2, 224 623 28.0

29 1.3 144 6.5 351 Sept. 1. 205 599 27.2

34 1.5 133 6. O 288
Sept. 8.
2, 266 596 26. 3
37 1,6 183 8.1

387
Sept. 15.
2, 223 562 25. 3

37 1. 7 170 7.6 389
Sept. 22.
2, 266 563 24.91 45 2.0 T 170

7.5 357 Holiday week. Number of mines working full time reduced by observance of the holiday. • Week of miners' election day. Many union mines closed on that day, • Many mines in union districts shut down on Apr. 2 in observance of the Eight-Hour Day. d Many mines shut down Aug. 10 in tribute to the late President Harding.

102

24. 5
23.3
24. 0
23. 5
24. 1
23. O
20.3
21. 2
20.0
21.9
22.6
21.9
24. 4
23. 7
21. 0
22.8
21.9
23. 1
23. 6
21.1
20.4
22. 1
22. 0
20.5
17.2
16.1
16. 3
13.6
14,3
17. 7
16.2
15. 1
14.8
15. 8
13. 1
17.1
17.5
15.8

226
180
153
125
122
161
140
131
155
161
130
151
115
135
122
126
118
123
149
134
157

343
288
268
280
303
322
306
245
294
269
327
294
284
309
265
311
326
268
308
344
402
395
403
375
400
323
359
347
396
365
402
412
327
343
382
449
396
414

14.0
11.9
11. 0
11. 7
12.3
13. O
12. 2
10.2
12.1
11.1
13. 4
12.9
12.1
13. 1
11.3
13. 2
13. 8
11.3
13. O
14. 2
17. 0
17. 3
17.6
16. 4
15. 3
12. 7
14.4
14. 5
16.0
14. 0
15.6
16.4
14. 7
15. 4
17.3
19. 8
17.8
18. 2

253
183
168
172
161
195
182
172
181
184
180
171
177
208
171
202
156
170
171
191
268
251
223
243
252
281
276
234
240
281
288
366
273
305
331
328
279
309

. 32
133
137
114
111
122
124
114
126
118
104
134
125

63
122
117
112
126
134
126
127
a 42
135
117
116
109
a 15
200
192
146
152

. 1. 3

5.5
5.6
4.8
4. 5
4.9
4.9
4. 7
5. 2
4. 9
4. 3
5.9
5. 3
• 2.7
5. 2
5. O
4.8
5. 3
5. 6
5. 2

5. 4
a 1.9

5.9
5.1
4. 4
4. 3
6.6
8. 4
7.8
5.6
5. 9

9.3
7. 4
6. 3
5. 2
5. O
6.5
5.6
5.4
6.4
6.7
5. 3
6.6
4.9
5. 7
5. 2
5. 3
5.0
5. 2
6.3
5. 6
6.6
7.4
7.9
7. 4
7. 6
7.1
7.8
10.5
11.9
11.3
9. 4
8.3
10.7
11.3
11.3
10.6

9.9
10.9

6. 6
7. 2
7. 2
7.9
11. 3
11.0

9.7
10.6

9.6
11.1
11.0
9.8
9.7
10.8
11.1
14. 6
12.3
13.7
15.0
14. 5
12. 6
13.6

d 41

d 1.6

329

TABLE 53.-Number and percentage of mines reporting weekly to the Geological Survey that were closed and number working part time and

full time, August, 1920, to December, 1923—Continued

• Holiday week. Number of mines working full time reduced by observance of the holiday.