From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Table of logarithmic values for variables N and y, governed by two related equations.
| Identifier | ExFiles\Box 77\5\ scan0145 | |
| Date | 26th April 1917 guessed | |
| -6- Log N = 2.9 + y/40 y = 40 log N - 116. N. y. N. y. 800 .12 1190 7.02 810 .34 1200 7.17 820 .55 1210 7.31 830 .76 1220 7.46 840 .97 1230 7.60 850 1.18 1240 7.74 860 1.38 1250 7.88 870 1.58 1260 8.02 880 1.78 1270 8.15 890 1.98 1280 8.29 900 2.17 1290 8.42 910 2.36 1300 8.56 920 2.55 1310 8.69 930 2.74 1320 8.82 940 2.92 1330 8.96 950 3.11 1340 9.08 960 3.29 1350 9.21 970 3.47 1360 9.34 980 3.65 1370 9.47 990 3.82 1380 9.60 1000 4.00 1390 9.72 1010 4.17 1400 9.84 1020 4.34 1410 9.97 1030 4.51 1420 10.09 1040 4.68 1430 10.21 1050 4.85 1440 10.34 1060 5.01 1450 10.46 1070 5.18 1460 10.58 1080 5.34 1470 10.69 1090 5.50 1480 10.81 1100 5.66 1490 10.93 1110 5.81 1500 11.04 1120 5.97 1510 11.16 1130 6.12 1520 11.27 1140 6.28 1530 11.39 1150 6.43 1540 11.50 1160 6.58 1550 11.61 1170 6.73 1560 11.72 1180 6.88 1570 11.84 | ||