======= ' ' K l; E N '' METERS 65 



carefullx th. --ti..i ..t theae on the gage height* and the 

 measurements, 



7. The availal>iliu ..I ..liservers or att.-n.l.mu, and th<-ir 

 lu.iliii. -ahnii* for tin- work. 



8. The most a|>|"-i" <..t. lyjie of gage, whether recording 

 MHMWonUng. 



ll no records are a\ H ning the diurnal fluctua- 



dons. MI. li records should be secured at once by installing a 



pulLllde .lilt. MM. ill, rr-lMrr (N-r Kr-M-lrf \... (,',',. |- 1 ;' . Kli. 



The results of this t.-t \%ill -h..\% N%h th.-r an automatic gage 

 m-t. illation i* necessary. 



9. For an ani.imati. water stage register, a survey of the 

 location decided upon. to iix the character ,t i m which 

 lie \\.-ll miM le .In-, tin- depth of the well, and the length of 

 tli uii.i^ tm .1 \. meal staff gage, the char.t sup- 

 port available and the length of gage rod required; for an 

 im-lnii-d staff gage, the cli.u.t. i.-r <>i tin- banks, the nature of the 

 support t..r tin- gage, aiul it- l-n^ih: for a chain gage, the 



support available and the length of chain required. 



lu. Tin- .ixaiLddf or rr.juir.-d >tnu-tures from whirh to 

 make in. nt-. 



If a bridge, a geiuT.il -k-t< h <! the \i.mii\ -h.. \MIIL' 

 espeeulK high water lines, and a >k< t< h .l the bridge itself, 

 showing tin- ni.iteri.il | \%ln, h it i^ |,uih. the length and number 

 of spans, and its height above water. 



If a cable, the length <>( |.m. the kind and height of sup- 

 ports available or required, and the foundation available 



thrm. 



Some |u.i< tical details* will be of assistance. The principal 

 sources of error in gaging >tre.un- l.\ em-rent metrr- are due 

 t< the i-Hr, t on the water stage of slack or nearlv slack water 

 in an\ p. tit ..I the cross-set- 1 ion. to h.nku.iter from dams or 

 nihi-r oli^tn: I..IH trilmt.irie-.. \\hieh mav <\IUM- the 



r stage to rise without a proportional increase in discharge, 

 and from oltrueiing ice. Do not choose a site immediately 

 above or below the junetion of two important brandies. Fig. 

 35 shows a gaging M..H..M uhere the re, onnoiMance was 



- .'..-. ,,-M fnmi n |w|er i-> C C 



\ 1 1 1 S i l ' 1 1 - r . 1 _ . . l s ..,.;, ^ . : s \ , , 



