476
T H E J O U R N A L OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y
Elliott apparatus for the determination of sulfur in gas showed that any of these apparatus is capable of giving satisfactory results if properly operated.
Vol. 5 , No. 6
of samples just before the water enters the first storage reservoir permits of counts being obtained before any after-growths are likely t o have occurred. The amount of available chlorin applied during the TABLEIV-PERCENTAGEOF TOTALSULFURCONDENSED IN SECOND TOWER period covered by the report of Stokes and Hachtel OF ELLIOTTAPPARATUS BURNING1.2 Cu. FT. OF GASPER HOUR Air supplied to was raised from 0.4 part per million, applied a t the apparatus bubbled start on June 15, t o 0.6 on June 23, and to 1.0 on through conc. (NH&COa renewed (NH&C03 renewed October 15. O n July 15, 1 9 1 2 , the amount was again every three hours every hour NHIOH raised, by order of the Commissioner of Health, t o 7.5 ' 0.6 0.1 6.0 0.8 ... 1.5 parts per million, and this amount has been main8.0 ... ... tained until the present time. TABLE V-PERCENTAGEOF TOTALSULFURCONDENSED IN ADDEDCONFrom June 11 t o November 1 2 , 1912, aluminum DENSER OF REFEREES APPARATUS sulfate, in amounts varying between 0.61 and I . o j Nothing added to NHlOH added to NHrOH + HzOz added grains per gallon, was applied t o the water as it ensecond condenser second condenser to second condenser tered the first storage reservoir. 1 .o 3.6 1.2 I1.l Shortly after the period covered by the report of 2.2 2.3 0.8 0.9 2.0 Stokes and Hachtel, after-growths in the storage ... 1 .o reservoir caused excessive bacterial counts. These Average 1. O 2.2 1.6 conditions maintained during the first five months Three important conditions for successful operation of the year, but about the middle of May the counts are: ( I ) A proper rate of combustion; ( 2 ) a strongly showed a marked diminution, and no further afteralkaline atmosphere in the condenser chamber; and. growths were observed, excepting during a few days (3) elimination of all rubber connections between the in September. The monthly averages of the results in bacterial burner and condenser. counts and B. coli tests, shown in a n accompanying BUREAUO F STANDARDS table, are taken from daily analyses. The counts WASHINGTON during the first six months were obtained on standard SOME RESULTS OF THE HYPOCHLORITE DISINFECTION agar a t 20' C., and during the remainder of the year OF THE BALTIMORE CITY WATER SUPPLY' a t 37" C. The B. coli averages were obtained from B y J. BOSLEYTIIOMAS AND EDGARA. SANDMAN tests made on portions of water varying b y a multiple Stokes and Hachtelz have reported the results ob- of ten from 0.001 cc. t o I O O cc., sufficient number of tained b y the hypochlorite disinfection of the Balti- tubes being used in each case t o secure a t least one more City water supply during a period extending negative and one positive test, excepting when no from the institution of the treatment on June I j , 191I , fermentation was obtained with I O O cc. The average t o October 30, 1911. They examined samples taken number of B.coli per cc. for each month was estimated from the untreated water in the impounding reservoir by considering the number of positive and negative and from the treated water after it had passed through tests in each dilution and following the method deeach of two storage reservoirs. The results of their scribed by Phelps before the American Public Health examinations showed bacterial reductions varying Association in 1907. Lactose bile was used as a n between 94.5 and gg per cent. They also showed initial medium, and Endo's agar was used for isolating average reductions in the Colon bacillus from j 7.5 the members of the B. coli group in pure culture, per cent positive tests with 0.1cc. of untreated water nearly I O O per cent successful isolations having been t o 1 2 per cent positive tests with 0.1 cc. of treated obtained by the use of this medium, whereas the water, and from 89 t o 40 per cent with 1.0 cc. The frequent encountering of spreaders on litmus agar greatest reductions were obtained with one part per and the fact that many of the acid-forming colonies million of available chlorin, when there were shown proved not t o be members of the Colon group seriously reductions from 86 per cent positive tests with 0.1 impaired the efficiency of this latter medium. No cc. of untreated water t o 9.5 per cent positive tests attempt was made until in the last two or three months with 0.1 cc. of treated water, and from roo per cent t o differentiate the four members of the Colon group; but this is now being done with the use of dulcite, in t o 37 per cent with 1.0cc. addition to the usual sugars, and morphological exThe period covered b y the following report extends aminations, and the results seem t o show a greater from January to December, 1912. I n addition t o the places sampled b y Stokes and Hachtel, we ob- vulnerability of the two B . coli organisms than of B . tained samples at the influent of the first storage aerogenes and B.acidi lactici. The results obtained by the use of the zoo temreservoir, after the water had passed through seven perature show much greater reductions in the bacterial miles of tunnel subsequent t o treatment. The time count than those obtained with the 37 O temperature, required for the water t o pass through this tunnel and we believe t h a t counts should be made a t the varies between 4.9 and 12.2 hours. While allowing higher temperature in addition t o those made a t 20'. sufficient time for effective disinfection, the taking The effects of the treatment of this water supply Paper presented at the Annual Xeeting of the American Chemical have been a very good reduction in the bacterial count Society, Milwaukee, March, 1913. of the water as i t enters the first storage reservoir, a Am. J . Pub. Health, April, 1912.
T H E J O URiVAL OF I N D U S T R I A L A N D E N G I N E E R I N G C H E M I S T R Y
June, 1913
477
MOKTHLYAVERAGESO F BACTERIALCOUNTSAND B . COLI TESTS IN THE BALTIMORE CITY WATER SUPPLYBEFORE AND AFTER TREATMENT First storage reserImpounding reserSecond storage reservoir efAuent 5-15 voir effluent before voir effluent 8-25 days days a f t e r trealTunnel effluent addition of hypoMonth after treatment ment 4.9-12.2 hrs. after treatment chlorite ,
-----*--.-.
~~~
Bacteria per cc. 20OC.
Jan. Feb. .Mar. April 11ay June
0.000 0.000 0.000 0.000 0.000 0 952
1.00 1.00 1.00 1 .oo 1.00 1.OO --
__
1.05
1.25
0.546 0.867 0.506 0.610 0.000
1.50 1.50 1.50 1.50 1.50
99.11
0.0712
99.46
2.80 40.0 42.6 26.0 24.2 7.81
370 42 23 67 31 33 36
99.01 95.71 X5 .08 87.25 96.22 88.58
0.0000 0.0020 0.0030 0,0025 0,095 0.064
100.00 99.99 99.99 99.99 99.61 99.20
38
91.97
0.0277
99.79
DEC , 1912,
SIIOlVlSG
-
TO
__
--a.
12 5 6 17 3 6 22 23 41 47 31 7
1
‘JI
47 26 36 24 40 47 149 339 364 187 99 68
7 9 3 2 3 3 24 35 29 30 25 10
39 23 20 22 23 41 107 217 312 138 61 66
2
_ _ _
_ _ _
_ -
1209
1420
1426
183
230
E
,z 5
180
$
:u
3 ’-
~
1069
0.016 0.0023 0 012 0.036 0.062 0.120
26,000 55,000 85,000 80,000 7,000 525
0.0037 0.0100 0.0120 0.0400 0.0790 0,120
0.0414
41,917
0.0441
__
_ _ -
c.
27 36 300 4s 24 35
-
B . Coli per cc.
__
TO
370 c. 180 210 225 55 26 30
0.0020 0.019 0.251 0,300 0.083 ,0014
__
0.0070 0.0300 0,178 0.300 0.096 0.0010
___
0.102
120
0.109
-
c r r _ &
8 9
3
g
8
43 16 37 35 65 41 78 217 469 241 87 91
___
Bacteria per cc. 20°C.
B . Coli per cc.
DECREASE I N brORBIDITY A N D .\fORTALITYSINCE THE USE O F HYPOCHLORITE 1912 1911 1910 Average 1906-1910
__i_
.z
a
__
1909
u
12 6 6 11 12 5 14 34 32 26 15 10
-
370
1908
1907
&
31 31 25 67 143 87 105 284 206 125 59 46
-
-
-
23.9
3
Jan. Feb. Mar. April May June July Aug. Sept. o c t. Nov. Dec.
s
__
TYPHOID FEVERI N BALTIMORE, JAX , 1906, Month
31,428
45
43
c.
1,100
1906
28,000 42,000 19,000 80,000 19,000 100
13 16
370 c. 4,200 550 450 240 875 325
.
99.99 99.99 100.00 100.00 99.66 99.16
116 10 12 81
5,100
-
Average
per cc.
Per cent reduction
0,0012 0,0022 0.0000 0.0000 0.094 0.33
1.70 2.56 7.21 31.4 27.1 39 0
- _ _
B . Coli
Bacteria per cc. 20°C.
95.91 99.51 99.17 99.46 99.88 96.61
1,100 1,600 14,000 1,800 9,500 2,400
Average
July Aug. Sept. Oct. sov. Dec.
B . Coli per cc.
Bacteria per cc. Per cent Z O O C. reduction
1”
P, 0:: ’-
3
V
V’
il
*
e
Q
--
40 25 30 22 31 46 110 473 398 359 251 106
7 30 49 42 37 26
136
235
16 3 5 4 5 6 11 20 24 23 10 9
and almost entire elimination of the members of the
B . coli group, the treated water during three months showing none of these organisms a t any time in I O O cc. The reduction in the number of cases of typhoid fever occurring in Baltimore during 191 2 is 31 per cent, compared with a n average of the number of cases occurring during the years from 1906 to 1910, and 24 per cent, compared with the number of cases occurring during 1 9 1 1 ,in the last six months of which the water supply was treated. We wish to acknowledge indebtedness t o Mr. Ezra B. Whitman, Water Engineer, and t o Mr. Emory Sudler, Engineer in charge of the improvement of the water supply, for an interest unusual with engineers not directly acquainted with the details of the laboratory work. WATER DEPARTMENT CITY O F BALTIXORE
WILD LETTUCE RUBBER’
7 11 12 4 2
55 31 35 44 56 34 89 280 241 170 104 62
- -
40 24 29 36 60 52 110 306 349 210 111 75
7 11 6 11 5 4 16 28 35 34 24 14
_ _
--
1891
1403
193
1201
a
11 3 5 8 7 8 4 22 31 28 19
-
47 28 33 37 30 57 98 198 212 190 77 76
9 7 11 10 3 3 15 22 18 12 9 17
- -
154
1083
136
8
as Dossible rubber producers. These are members of the genus Lactuca (Wild Lettuce), one of these species, L.Canadensis, being a native while the other, L. Scariola. is of European origin. Both are widely distributed and in some sections are very abundant and often regarded as troublesome weeds.
Lactuca Canademis.-A native biennial plant found growing everywhere across the continent from Oregon to the Carolinas. A vigorous, robust plant, three to twelve feet high; stems stout, hollow, purple; leaves, large, irregularly cut and toothed, dull green; flowers small, numerous, yellow to white; seeds small with usual cottony appendages which aid in its distribution; odor strong, acrid. All portions of the plant, especially the stem, secrete, when bruised, a n abundance of thick latex which rapidly coagulates to a yellowish semi-solid. Found in damp situations, growing upon rich soil, especially on newly cleared lands. Known as “Fireweed,” Trumpetweed.” I ‘
B y CHARLESP. F o x
We have in the Central United States, two representatives of the Conzpositae which might be regarded Paper presented a t the Annual Meeting of the American Chemical Society, Milwaukee, March, 1913.
Lactuca Scario1a.-A naturalized annual from Europe. Stem three to four feet high, erect, branching, armed with stiff, sharp spines; leaves opposite, oblong, sessile or clasping, armed ; flowers. numerous.
