In Vol. 5, page 307, you have published i table giving the contents of a log in boarc measure of 12, of 14, and of 16 feet long, tron 12 to 48 inches diameter. In the same vo 1 lume, on page 322," M. W. B." corrected th table prepared by " M. J. B.," and gives us ; rule tor oi ly one length of logs, and asserts i to be a true mathematical one—that he ha found it correct by sawing many tijousam feet of plank. All this is good as far as i goes, but it is of little use in this country, fo we have to saw logs for fence posts of 4 fee length, some 4 feet; in tact, all lengths, to 2' ' feet. We have prepared the following tab! which suits us much better; it may be of us to many of its readers. I copy this from on I prepared for the pages of my volume for th ) use of operatives. It is the result of the following formulae , —Multiply the diameter by 31416 for the cir i cumference; multiply the diameter by "707106 , for the side of the square inscribed in the cir J cumference or circle, this ? roduct, squarec gives the area contained in the square, whic 5 divided by 6 and multiplied by 12, gives th 5 board measure in one foot of the bg; multi f ply this by the length of the log in feet, th , result is the boards from the square of the lo ; The division by 6 is only for the square of th b log, for one-fifth of the log is lost in sawin r boards one inch thick. i The first column is the diameter of the lo 1 in inches; the second column is the girth c t circumference in feet and hundredths; th s third column isthe area of the end of the lo s in square feet and hundredths; the fourth c( lumn is the side of the square it will make in feet and hundredths; the fifth column is the area ot the square in square teet and hundredths ; the sixth column is the amount of board measure contained in one toot ot length of the square, after the saw-dust is deducted. 2 ? -3 p I :s ! - s ir g-o ?g. ?2, 3 One Two Three Four Five Six 9 2*34 -63 -52 '27 2*76 10 2-61 -64 -58 -34 3*48 11 2.87 -66 -64 '42 4*20 12 3"14 -78 -69 '45 4*56 13 3'40 -99 -76 '58 5*80 14 3 89 1-03 -83 '68 6.84 15 3'93 122 -87 '75 7'54 16 4-18 1*39 -94 '88 8*83 17 4'49 1-58 1"00 1*00 10 00 18 471 1-76 1-06 1-12 11 20 19. 4'97 1-96 1-11 1*25 12 50 20 5-21 217 117 1-38 13 80 21 5*49 2'40 1-23 1*51 1519 22 5-75 2 63 1*29 1*66 16'60 23 6 01 2-87 135' 182 18*22 24 628 314 1-41 1*98 19 88 25 6'54 3-40 1*47 2 16 21*60 26 6-79 3'76 152 232 23 20 27 7-06 3-97 1*59 2'52 25 27 28 7*32 4-26 1*65 2'70 27 06 29 7-58 4*07 1*70 289 28 90 30 7 85 4-90 1*76 3 09 30-97 31 811 5-22 1-82 3 31 3312 32 8'37 5'57 188 3'53 3534 33 8'63 5-93 1*94 3 76 37*63 34 8-89 629 200 4*00 40*00 35 915 6'67 2*06 4*24 42 39 36 9-42 7 06 212 4*59 45*90 37 9-68 7-45 218 475 47 52 38 9 84 785 2'23 4 97 49*80 39 10-21 8-29 2-29 528 5280 40 10-46 8'71 2:35 5 52 55-22 41 10-71 9-14 2-41 5-80 58 08 42 10-99 9-62 2'47 6-10 61*00 43 11-25 10.07 2.53 6'40 64-00 44 11-51 10-54 2-59 6-70 67*08 45 11*78 11-04 2'65 7 02 70-22 46 12-03 11*53 2'71 7*34 73 44 47 12 29 12.03 2.76 7 64 7645 48 12-6 12-56 2 82 7*95 79-52 49 1282 13-07 288 829 82 94 50 12-98 13-49 2 94 8'64 8643 51 13.35 14-18 3-00 9 00 90 00 52 13-60 14-73 3 06 9-36 93 63 53 1386 15-31 3 12 9-73 97 34 54 14-13 1590 3 18 10-11 101-12 55 14*39 16-46 3-24 10-49 104-97 56 14-65 17-08 3-29 10*82 108 24 57 14*92 17*72 3'35 11*22 112-22 58 1517 18-33 3 41 11*62 116-28 59 15-43 18 64 3-47 12*08 120-82 60 15-70 19-63 3*53 1246 124.60 To use the above table, multiply the length of the log in feet by the number in the 6 th column, on a line with the diameter in the first column, tor the quantity of boards the log will make; but when the log is of more diameter than 2 feet, boards may be sawn after the square of the log. To ascertain the thickness of the slab after the square, subtract the number in the 4th column from the diameter in the 1st column, then divide by 2, and the result is the thickness of the slab. To ascertain the whole contents of the log, multiply the number in the 3rd column by the length oi the log, it gives the cubic feet contained in the log; this multiply with the weight of the cubic foot in any table, we have the weight of the log. We have some logs in our yard 3i feet and upwards, from 9 to 11 feet long; we work only by the table: What number of feet of boards, one inch thick, Will be in a log 3 feet 10 inches diameter and 9i feet long ? Column No. 6 on the line with 46 diameter, we have 73'44X 9-5=697*684-313-5=1011*18lt. of inch boards. The 313-5 can be sawed out of the slabs, they are '56 foot thick, as follows:—Column 4, we have 2-71—3-833=l*122=-56, from which three boards can be taken of from 14 to inches wide, which makes the above. JamSs Sloan. Sloan's Mills, Floydfork, Shelby Co., Ky.

This article was originally published with the title "Table of Lumber in Logs" in Scientific American 8, 10, 75 (November 1852)

doi:10.1038/scientificamerican11201852-75b