DUST PREVENTION AND ROAD PRESERVATION, 1916. 
TABLE 3.—Location of guard-rails. 
Left. 
Station 1+82to Station 4+79 
Station 14+71 to Station 16+60 
Station 20+-00 to Station 25+78 
Station 40+40 to Station 42+ 26 
Station 56+ 90 to Station 57+94 
Station 58+ 24 to Station 59+68 
Station 63+00 to Station 64+00 
Station 66+41 to Station 72+60 
Right. 
Station 1+4+41 to Station 4+66 
Station 22+-59 to Station 24475 
Station 24+88 to Station 26+00 
Station 40+10 to Station 43+76 
Station 55+06 to Station 59+06 
Station 63+ 25 to Station 63+ 65 
Station 67+38 to Station 72+ 34 
Station 77+84 to Station 79+ 28 
Station 77+63 to Station 79+ 63 
Total, 4,519 linear feet. 
TESTS OF MATERIALS. 
Tas LE 4.—Physical properties of trap rock used in the surface construction. 
RMCeRMe OTL VILY 2... Nees SSL MER ras on eas OO es Sse 3.00 
Weorelsper/ cubic 100tss. 2) 25 Jas PSN SE ee eee pounds.. 187 
Wrarnetapsorbed per cubic:foot. -24 fi see i. 2: 4-2 lsh healt Se dole 43 
eC EM OM CAT ae tose cree cds ee cera tpt Ete MSc ces op sc ate ats ae eo 2.6 
ipcurbecoeictent, Ol; Watson te sree ea ace ass eke pees Se aaa oe eS 15.5 
LE TUDES Ss SER BEE a eee ee Omen Pincers een ot heme eee ae 18.3 
“LS ELETT C38 See SAR ne ene tna ee ey ene eee = Eas Huey woe 13 
emalcariimr ay UU ss. fe Stes SN Oe Ee ate ee. Pe ltr ke be hn 3 ahha Ae, Fair. 
Tasie 5.—WMechanical analysis of gravel and sand used in the surface construction. 
Retained on 2 inch screen 
Passing 2-inch, retained on 14-inch screen... .---------- 
Passing 13-inch, retained on 1}-inch screen... -.---.-.---- 
Passing 11-inch, retained on 1-inch screen....-----.---- 
Passing 1-inch, retained on #-inch screen...-.-.-.-.---- 
Passing 2-inch, retained on 4-inch screen...-----.------ 
Passing 34-inch, retained on +-inch screen...-..-.---.---- 
Passing +-inch, retained on 10-mesh sieve. ...-.--.-.---- 
Passing 10-mesh sieve retained on 20-mesh sieve...-.--- 
Passing 20-mesh sieve retained on 30-inch sieve--.- -..-- 
Passing 30-mesh sieve retained on 40-mesh sieve-.-..--. 
Passing 40-mesh sieve retained on 50-mesh sieve... ---- 
Passing 50-mesh sieve retained on 80-mesh sieve.--.---- 
Passing 80-mesh sieve retained on 100-mesh sieve-.--.-- 
Passing 100-mesh sieve retained on 200-mesh sieve... --- 
Passing 200-mesh sieve 
Screened Pea-gravel 
Brave! for Clean sand Sreeny, for gravel 
penetration| [oT experi- Ge eri- experi- 
Spe ments Nos. 2a) ments Nos. 
peri Pettis ments Nos. 5, 6.7 
ments Nos. ° 7 and 8. ae 
5 and 6. and's. 
Per cent Per cent. Per cent. Per cent. 
BY (68 1c| PERE ge Set Ips Sei icine (einer: SS 
1D) eatanecicecclacceaslmasee| (emcee ome 
205) | asee ee Ssisse BM asian ee see 
10 SU Aeoeceee ce Of ease a= 
el eres CEN) emegesecosec 
SRE Ce| Honecoe orcs 14.9 9.9 
sieaweest.se| Fs ede 23.6 50.4 
oie erste |e oe Se 16.8 34.2 
Sateen sees U4 6.1 525 
Ne ee te 19.6 BBY | See eee 
bio Seese 2 25.6 By al ace eerie aoe 
pS = rare am 22.4 QO |e oseenetee ae 
ERA Sos ae Wears 26 )"sse cee oes 
Be Aa oe 1.6 SOULE Semieemece ae 
Se Se aa 5.0 230i Setree=sosee 
eich eee eee 1.4 1 Et | ee Se 
100.0 100.0 100.0 100.0 
