I'ln- maximum .-kin .sh. id 1. 1 



7t'..!>00 Hi-. was (J135 Ibs. pci gob. 



t I'lir li'lai :i'ii undi r :i load of ( l,(l(lll ids. :il tin' r.-nii. 



1.7 in.. and taking (.In- effective depth "I' (In- In a 111 In In- 1 1.5 in?-., ill 1 

 mi liii.' maximum >kin ennipn - iil!'5 Id-, [in 



-'|iiaie inch, (ho OOITMpOnding skin tensile sin-- deuiu -221 Id 

 M|ii:iic inch. 



As-liming till- ordinary l:i\v In ln>M good for the whole "I 

 live depth, the iii;i\iiiiiini .-kin .-Ires- would lie 7n'(>2 Id-, per square 



ineli. 



CHu CO efficient nf ei;i-;t'-ll \ . .'is ill (< TII lined dv 'HI incl'e.'l.-e ill (I, 



i nf lllin. d.-tween tlic loads of 11,00(1 1111(1 22,000 Id-., i- 

 1, !!>'.. 711 Id-. . a- determined dv an increment of the deflection .,! 



.33-in. between tlu- loads 10.0011 Ids. and :52,oon Ibs., it i- 1,16 



ids. : and a- deduced from an increment in tde deflection of .20 in . 

 the mean between .2S5-iu. ;ind . 205 in., the increments bet.v.een tin 

 loadl of 5. IllHi and 2:.,000 Ids. and 10, 000 and 30,000 Ids. respectively, 



it is i,2<i:;.5oo Id-. 



Table II show.-, the several readings. 



The total weigh! of the I m on N'ov. 25th, the date of test, was 



.'!.'il Id-. '.} ii/.s., or 32.8 Ibs. per cubic foot. After cutting off the end-, 

 the weight of a length of feet WAS 202 Ibs. 5 ozs., or '.','.} A Ibs. p. i 

 cubic foot. The total weight of the beam on October :!id w a- .'!:!!( Id-. 

 !) M. 



Beam X X V from Trestle 111 (i. This deain was te-ted Nuv. 28th. 

 1 S'.i:;. with the annular ring- a- in Fig. 5(1, and showing the heart 

 on one. of the f, 



It eoniained one vertical bolt hole, several kco ts , and many season 

 cracks. The grain was snaight. 



Tin.- load upon the beam was gradually increased until it amounted 

 to 42,900 Id-., when a lar_:e splinter drokc. off on tl:e ten.-ion fee, and 

 the beam failed by longitudinal shear, as in Figs. 51, 52. 



The maximum skin stress corresj ond'ng to this breaking load is 

 4613 Ibs. per square inch. 



The CO efficient of elasticity, as determined by an increment in the 

 deflexion of .:;:;.') iii. between the loads of l,n()() Ids. ami 20,000 Ids., 

 i- !U'.i,720 Ids. 



Table I show- the readings for the several loads. 



The total weight of the be mi on October .'ird was 122 Id-., or 34.11 

 Ids. p.'i- cubic foot, and on Nov. 2^td, the date of test, the weight was 

 40(i Ids., or !!.'!. 11 Ids. per cubic foot, showing a lo.-s of weight in tlu 

 Laboratory at the rate of .2.'!7-ld-. per cubic loot per day 



The time occupied by the test was HO minutes. 



17 



