The Houston daily post. [volume] (Houston, Tex.) 1886-1903, 1902-09-11

/ depends the water rates charged to the
| public
! QUANTITY TO BE PROVIDED FOR.
! would recommend per capita the
/ amount OF 100 gallons daily each, lnclud
! ing waste. This for population OF 10000
would amount to 100000 gallons. Owing
/ to the variation in consumption dndepend.
/ ent OF fire supply during certain seasons,
! etc, we will add 80 per cent, making the
/ supply 15,Oo0,00O gallons. or 400 cubic
! feet per minute.
! We will assume twenty fire streams to
! he in use at one time OF thirty cubic feet
! per minute each, or 225 gallons per min
ute. or 600 cubic feet per minute. The
I combined rate Of flow hence Is 20O0 cubic
\ feet per minute, requiring force main
/ thirty inches In diameter, losing $40
/ feet head per 1000 and a velocity of flow
| OF $40 feet per second. for an approx
/ mate calculation.
! FIRE EFFICIENCY FROM F1REMEN's
AND INSURANCE STANDPOINT.
/ systems Of Water Works
| /. Gravity works come first because they
are always ready.
| ?. Pumping TO distributing reservoir large
enough to hold one weeks supply plus re-
serve sufficient for six hours supply foi
/ greatest probable fire.
! 3 Pumping to large standplpe of sur
/ hcient height to give ample pressure.
! 4. Pumping to small standpipe OF sui.
hclent height to give ample pressure.
! 3, Pumping direct into the mains without
standplpe or reservoir.
The Principle of Fire streams.-The fol
lowing points OF information were brought
/ our at the Massachusetts state Flrsmen' $
| association in September. 1900 and are
well worthy OF consideration, There n
| probably no subject pertaining to the fire
service so Important 70 be thoroughly IN
usrstoou, ana one that hremen generally
understand so little, as that OF pressure
and distances that different sizes OF
streams can be projected under different
pressure AT first thought. one might reas,
"no2H suppose that the more pressure ap-
phed TO a given size Of nozzle the greater
me distance the stream would reach ana
lhat any Increase in size, without any IN
grouse Oh pressure could only be proper
lolalelE less IN distance. II will be found
lAdI the opposite Of this reasoning proves
true In hydraulics. AS strange as If may
seems 10 some, pressure above a certain
point on any size Of nozzle produces re.
sun me very opposite. Science tells us
llul an increase of pressure means simnlv
an Increase Of velocity. and thar the re-
slstance Of the air To the stream is In pr0.
portion 10 Its velocity. Such Ia The nefure
OF water. that the instant its velocity is
increased II meets with an added resist
ance OF the air and begins to stlip or as
the nremen call II, tear itself to pleces +.
Water not being solid, but composed OF an
mantle number OF particles that move with
great freedom among themselves the IN
srant It's velocity is increased meets win
an ADDED resistance from the air and be-
giis TO strip sooner. ii lacks Conference ana
having been previously taxed to It's utmost
20 reach the end, now, In spite of Increased
quantity Of Sater finds itself unable ia mold
tcPt ther, and thus takes advantage of ITS
auueu weight or as the hremen express
y, tears itself to pieces and fails TO reach
.rss pr ssure.
MAXIMUM HEIGHT or STREAMS.
In 'Dox" hydraulics IS a table ety,n,
the maximum height that each size of let
can be forced under different heads from
Ten TO 400 feet and IN sizes of streams
nom one-eighth Of an inch. increasing eacn
size in eighths OF an inch up to two inenes
IN diameter.
In each of the 200 or more different tes,s
under the same head. Ia each size ~ tne
slE, OF streams liner tases substontiat ~.
cIease or distance 81 made. lgk,. Inv az
ample me hVe-eishth inch stream. the may.
ner',io,, tsnt TINS size can be 1orced per.
pen9icularly In stii air, under 2ist fSet
feet. - P'Nssure - lVO
Now what Is the result il the pressnrn %
,,,,,.,.1@.o ttNu tlEul@ -slK pounds ~ lyui
bbe eais AZ the pressure increases me
$3.50 ,esss eimihlshes to seYenty-nve fept when
,eeonlns l5V pounds. Again to shov tbs
e at1ss lAAt can be obtained IRON, me
rs. s'A pounds pressure by simply An.
SttAslhs tne Size OF the nozzle nh nndcr
s-e same pressure, the three-fourth tncn
,"eneu ITO leet, the one iuch lyI feet m,
~ anu oheionrth Inch 100 feet. mo one
s st, uHe-Ahl men l5s feet the threa-
t0e.sns lhSh lob feet, etc. Thus mo same
~, e'suis tAat sends the tve-eghtns inrh
80 49, iSet hlsh sends the two inch slxry.nine
-, A'-n'4 On the other hand ire is,,
tv 1 tAat cur down the nvv-eirhths ine6
s',enlh ItoM 100 TO seventy i've feef sends
wv ineh stream $50 feet high. or an i'm
Ky suleht ~ perpendicular distance or
- Lett, besides delivering over an ner
al ssut larger volume OF water. 10 carry ms
~ ,.s ms OF an Inch stream stan f,irtbsr
WIS round that when l8U ponnds ni.es
s suIs was applied a stream seyentv-Hve fset
49, was tne result, q pressure Of fortv
beisS. POUNDS gave the same result in
~ ST. SIT aud with a pressure OF l5l noI,nds
~, ns sn'Am was reduced to nifty feet yyben
nt,ttttts SIX pounds would have accom-
,,as lhe same height; while me lal
e,..ta pressure will send q one and one.
~ ~ theh stream l9S feet A.-h. the ono
~ ohe mar Inch stream 222 feet hirn
80. ~ ~, ahu thfee-fourtha inch stream 34l
MA n'sn' ana the two inch stream 255 feet
bsba tne TWO Inch stream 31 feet
sc.rs snAh the Isl pounds can possibly
tne nre-eighths Inch stream
s.se. ensse results OF diltances ana pres-
sssss- syn III Be Produced N any rye. de.