430 VALUATION, DEPRECIATION AND THE RATE-BASE 
TABLE 30. THE PROBABLE USEFUL LIFE OF VARIOUS 
ARTICLES (Continued) 
Description. Bo Bestar Authority. Remarks. 
Track (continued) 
special work............... 12.85 Chi. UU. T-iCo- Chi. Union Trac. Co. Case. 
special work............... 13.86 Stone & Webs. Chi. Union Trac. Co. Case. 
EGR Sa Saba ata val ct Tea et 20 Trac. Val. Com. Chi. Con. Trac. Co. Case. 
railroad rails, new.........} 25 26% Cal. R. R. Com Stockton Term. & East. Case. 
railroad rails, relay ........ 15 48% Cal. R. R. Com. Stockton Term. & East. Case. 
R. R. rails and track fast.. 40 Gillette Gt. Nor. & N. P. Appraisal. 
railroad track fastenings.. | 123 Cal. R. R. Com. Stockton Term.& East. Case. 
railroad ties... Lod ni ES Gillette Gt. Nor. and N. P. Appraisal. 
railroad ties, redwood.....1 16 Cal. R. R. Com. Stockton Term.& East. Case. 
railroad ties, creosoted....., 19.35 O. Chanute Houston & Texas Cent. R. R. 
trestles and bridges....... | Io Cal. R. R. Com. Stockton Term.& East. Case. 
ballast CTO Cal. R. R. Com. Stockton Term. & East. Case. 
frogs and switches........., 25 367% Cal. R. R. Com. Stockton Term. & East. Case. 
cast-iron culverts.......... 16 Cal. R. R. Com. Stockton Term.& East. Case. 
Transformers... sisi sioioe iene 15 St. L. P. S.C. Union Elec. L. & P. Co. Case. 
15 Wis. R. R. Com. Quoted by Henry Floy. 
station SETVice............. 20 Wis. R. R. Com. Quoted by Henry Floy. 
SEALION ale «ins Satan iete xis a hates 25 S.J. L.&P. Cor. Cal. R.R. Com. rate hearing. 
line. hl aia, he 20 10% Cal. R. R. Com. Calis. E. C. vs. Napa Val. E. 
Co. 
distribution... Lil. | 20 ($r.00kw. P. G. &E. Co. S. F. rate hearings, 1913-14. 
DOWELL tol byob leh ll oe 20 $ .50kw. P.G.&E. Co. S. F. rate hearings, 1913-14. 
static transformers. ....... 15 Hammond Jour. Inst. E. E., 1907. 
Tunnels 
powerplants. i... 0... LLL E50 S.J. L.&P. Cor. Cal. R.R. Com. rate hearing. 
Turbines 
SLEATTY | aleve halos lateretd oe JEERYS St. 1. P.:S.\C. Union Elec. L. & P. Co. Case. 
Shennan Sa es 20 Wis. R. R. Com. Quoted by Henry Floy. 
SEEATL a  eale Tel otal] 20 Hammond Jour. Inst. Elec. E., 1907. 
LRAT Le ol le tebar el ainiale ata lates 30 1¢1b. P.G.&E. Co. S. F. rate hearings, 1913-14. 
VAULT nl sin a ae aia mol tal wa 30 Wis. R. R. Com. Quoted by Henry Floy. 
water-type prior 1900. ..... 25-40 Foster ‘“ Eng. Valuation,’ etc. 
water-type after 1900....... 30-50 Foster ‘ Eng. Valuation," etc. 
Washers (gas plant) 
CARLTON tals ae fr etal 40 Wis. R. R. Com. Quoted by H. A. Foster. 
Water gas machines. .......... 30 Wis. R. R. Com. Quoted by H. A. Foster. 
Watt meters 
SETVICE lv ool le di diatetiln tara ata tere MIT O=T5 Foster ‘“ Eng. Valuation,’ etc. 
Wells ; 
WALE «et ais aia dntora 30 S.J]. L..& P..Cor. Cal. R. R. Com. rate hearing. 
water, driven or drilled... 50-75 Foster ‘ Eng. Valuation,” etc. 
water, large open masonry. 75-100! Foster “Eng. Valuation,” etc. 
water well pumps.......... 10 S.].L.&P. Cor. Cal.R.R.Com.rate hearings. 
gas wells. Lire a0 0 LLL TO 0% Cal. R. R. Com. Midway Gas Co. et al. Case. 
gas well drilling equip... .. 10 25% Cal. R. R. Com. Midway Gas Co. et al. Case. 
Wharves and docks. ........... 33% Gillette Gt. Nor. & N. P. Appraisal. 
Wire 
BETIAY viet timate tot 20 St. .L.P. S.C. Union Elec. L. & P. Co. Case. 
Serial COPDET a ve oir sieininivi sins 15 Chi. Tel. Com. Chicago Telephone Com.