The filtration of public water-supplies / Third edition, revised and enlarged.

by Allen Hazen

By plotting the heavy-faced figures we find that 10 and 60 per cent are respectively finer than .055 and .46 millimeter, and we have effective size .055 millimeter and uniformity coefficient 8.

The effective size and uniformity coefficient calculated in this way have proved to be most useful in various calculations, particularly in estimating the friction between the sands and gravels and water. The remainder of the article in the Report of the Mass. State Board of Health is devoted to a discussion of these relations which were mentioned in Chapter III of this volume.

APPENDIX IV.
FILTER STATISTICS.

STATISTICS OF OPERATION OF SAND FILTERS.
Place.	Year Ending.		Total Quantity of Water filtered for One Year. Million Gallons.	Million Gallons Daily.	Area of Filters in use, Acres.	Average Daily Yield, Million Gallons per Acre.	Area of Filter Surface cleaned in One Year, Acres.	Period, Million Gallons per Acre filtered between Scrapings.
Altona	March,	1895	1,620	4.44	3.08	1.45	31.0	52
	March,	1896	1,730	4.75	3.08	1.55	48.5	36
	March,	1897	1,960	5.40	3.08	1.75	44.0	45
	March,	1898	1,940	5.30	3.08	1.72	36.5	53
Amsterdam, River	Dec.,	1894	1,390	3.80	5.43	0.71	23	62
	Dec.,	1896	1,490	4.08	5.43	0.75	48	31
	Dec.,	1897	1,600	4.40	5.43	0.81	30	53
Amsterdam, Dunes	Dec.,	1894	2,330	6.40	4.94	1.29	116	20
	Dec.,	1896	2,360	6.50	4.75	1.37	90	26
	Dec.,	1897	2,290	6.25	4.75	1.31	109	21
Ashland, Wis	Feb.,	1897	398	1.09	0.50	2.18	4.83	83
Berlin, total	Mar.,	1896	13,000	35.60	25.10	1.42
	Mar.,	1897	12,900	35.40	25.10	1.40
	Mar.,	1898	13,200	36.20	27.00	1.34
Bremen	Mar.,	1895	1,190	3.27	2.51	1.31	50	24
	Mar.,	1896	1,220	3.34	3.21	1.04	32.5	38
	Mar.,	1897	1,280	3.50	3.21	1.09	25.2	50
	Mar.,	1898	1,400	4.10	3.21	1.28	34.0	41
Breslau	Mar.,	1895	2,840	7.80	5.12	1.52	45	64
	Mar.,	1896	2,960	8.10	5.12	1.58	40.0	74
	Mar.,	1897	2,990	8.20	5.12	1.60	37	81
	Mar.,	1898	3,060	8.40	5.12	1.64	43	71
Brunn	Dec.,	1896	1,110	3.04	1.62	1.87	8.6	128
	Dec.,	1897	1,190	3.25	1.62	2.00	9.1	131
Brunswick	Mar.,	1895	815	2.23	1.48	1.51	14.8	55
	Mar.,	1896	840	2.30	1.48	1.56	13.3	63
	Mar.,	1897	820	2.25	1.48	1.52	13.7	60
	Mar.,	1898	870	2.38	1.48	1.61	11.9	73
Budapest	Dec.,	1892	7,360	20.20	3.00	6.70	254	29
Copenhagen	Dec.,	1895	2,330	6.40	2.88	2.22	45	52
	Dec.,	1896	2,490	6.80	2.88	2.35	52	48
	Dec.,	1897	2,580	7.10	2.88	2.47	54	48
Dordrecht	Dec.,	1894	365	1.00	0.56	1.79
Frankfort on Oder	Dec.,	1895	310	0.85	0.37	2.28	2.9	107
	Dec.,	1896	325	0.89	0.37	2.40	7.4	44
	Dec.,	1897	356	0.98	0.37	2.65	8.8	41
Hamburg	Dec.,	1894	11,450	31.40	34.0	0.92	350	33
	Dec.,	1895	11,700	32.10	34.0	0.94	275	43
	Dec.,	1896	11,500	31.70	34.0	0.93	266	43
	Dec.,	1897	12,000	32.70	34.0	0.96	285	42
	Dec.,	1898	11,900	32.60	43.0	0.76	246	48
Hudson, N. Y.	Dec.,	1892	697	1.91	0.74	2.58
	Dec.,	1893	543	1.49	0.74	2.01
	Dec.,	1895	535	1.46	0.74	1.98
Ilion, N. Y.	Feb.,	1899	182	0.50	0.14	3.57	1.40	130
Königsberg	Mar.,	1895	1,060	2.90	2.70	1.07	38.5	27
	Mar.,	1896	1,085	2.97	2.70	1.10	35.0	31
	Mar.,	1897	1,085	2.97	2.70	1.10	41.0	27
	Mar.,	1898	1,140	3.12	2.70	1.16	44.0	26
Lawrence	Dec.,	1894	1,050	2.88	2.50	1.15	10	105
	Dec.,	1895	1,097	3.00	2.50	1.20	27	41
	Dec.,	1896	1,101	3.02	2.50	1.20	30	37
	Dec.,	1897	1,114	3.06	2.50	1.22	41	27
Liverpool	Dec.,	1896	8,520	23.40	10.92	2.14	158	54
[53]London, all filtersbut not includingground water	Dec.,	1892	65,783	180	109.75	1.64		90
	Dec.,	1893		195	116.00	1.68
	Dec.,	1894	68,700	188	117.00	1.60
	Dec.,	1895	76,900	210	123.75	1.70
	Dec.,	1896	72,482	198	123.75	1.60
	Dec.,	1897	73,340	201	125.00	1.61
London, Chelsea	Dec.,	1897	5,370	14.70	8.00	1.85
E. London	Dec.,	1897	18,000	49.00	31.00	1.58
Grand Junction	Dec.,	1897	8,560	23.40	21.75	1.07
Lambeth	Dec.,	1897	10,370	28.40	12.25	2.30
New River	Dec.,	1897	15,750	43.00	16.50	2.60
Southwark & Vauxhall	Dec.,	1897	14,800	40.50	20.50	1.98
West Middlesex	Dec.,	1897	8,910	24.30	15.00	1.61
Lübeck	Mar.,	1895	1,520	4.15	1.40	2.95	16.2	94
	Mar.,	1896	1,600	4.38	1.40	3.13	24.4	66
	Mar.,	1897	1,650	4.50	1.40	3.22	27.0	61
	Mar.,	1898	1,750	4.80	1.40	3.42	38.5	45
Magdeburg	Mar.,	1895	1880	5.15	3.76	1.37	47.5	40
	Mar.,	1896	1950	5.35	3.76	1.42	65.0	30
	Mar.,	1897	1880	5.15	3.76	1.37	59.0	32
	Mar.,	1898	2070	5.66	3.76	1.50	63.0	33
Mt. Vernon, N. Y	Dec.,	1895	493	1.35	1.10	1.22	7.3	68
	Dec.,	1896	608	1.66	1.10	1.51	9.2	66
	Dec.,	1897	808	2.21	1.10	2.00	16.6	49
	Dec.,	1898	933	2.56	1.10	2.34	18.4	51
Posen	Mar.,	1895	305	0.84	0.70	1.20	10.3	30
	Mar.,	1896	346	0.94	0.70	1.35	10.4	33
	Mar.,	1897	325	0.89	0.70	1.27	10.1	32
	Mar.,	1898	360	0.99	0.70	1.42	9.6	38
Poughkeepsie	Dec.,	1892	696	1.91	0.68	2.81	14.0	50
	Dec.,	1893	667	1.83	0.68	2.70	12.0	56
	Dec.,	1894	633	1.73	0.68	2.55	14	45
	Dec.,	1895	686	1.88	0.68	2.77	14	49
	Dec.,	1896	664	1.82	0.68	2.68	9	73
	Dec.,	1897	615	1.69	1.36	1.24
	Dec.,	1898	611	1.67	1.36	1.23	10.88	57
Rostock	June,	1897	560	1.54	1.11	1.38	9.3	60
	June,	1898	625	1.71	1.11	1.55	9.0	70
Rotterdam	Dec.,	1893	4850	13.30	6.30	2.11
Stettin	Mar.,	1895	1130	3.10	2.26	1.37	26.5	43
	Mar.,	1896	1030	2.83	2.26	1.25	15.5	66
	Mar.,	1897	980	2.70	2.26	1.19	16.1	61
	Mar.,	1898	1020	2.80	2.26	1.24	20.3	50
Stockholm	Dec.,	1895	2375	6.50	2.78	2.33	70.0	34
	Dec.,	1896	2500	6.85	2.78	2.45	68.0	37
	Dec.,	1897	2750	7.50	3.60	2.08	76.0	36
Stralsund	Mar.,	1897	215	0.59	1.11	0.53	16.0	13
	Mar.,	1898	210	0.58	1.11	0.51	17.3	12
Stuttgart	Mar.,	1895	1040	2.85	1.46	1.96	13.7	76
	Mar.,	1896	1220	3.34	1.66	2.04	17.7	69
	Mar.,	1897	1270	3.48	2.32	1.50	18.7	68
	Mar.,	1898	1320	3.60	2.32	1.54	20.2	65
Utrecht	Dec.,	1896	510	1.40	0.60	2.33	31	16
Zürich	Dec.,	1891	2010	5.50	0.84	6.50	8	250
	Dec.,	1892	2150	5.90	0.84	7.00	10	215
	Dec.,	1893	2310	6.38	1.19	5.35	13	177
	Dec.,	1894	2250	6.15	1.19	5.18	17	133
	Dec.,	1895	2460	6.70	1.19	5.62	27	91
	Dec.,	1896	2360	6.45	1.66	3.88	30	79
	Dec.,	1897	2500	6.84	1.66	4.13	35	71
	Dec.,	1898	2730	7.50	1.66	4.50	47	58

PARTIAL LIST OF CITIES USING SAND FILTERS.
Place.	When Built.	Population. 1890.	Area of Filters.	Number of Filters.	Average Daily Consumption.
UNITED STATES.
Poughkeepsie. N. Y.	1872	24,000	1.36	3	1.67
Hudson, N. Y.	1874	9,970	0.74	2	1.50
St. Johnsbury, Vt.	187(?)	3,857	0.14	3	0.70
Nantucket, Mass.	1893	3,268	0.11	1	0.09
Lawrence, Mass.	1893	44,654	2.50	1	3.00
Ilion, N. Y.	1893	4,057	0.14	2	0.50
Mount Vernon, N. Y.	1894	10,830	1.10	3	1.66
Grand Forks, N. D.	1894	4,979	0.42	1	....
Milford, Mass.	1895	9,956	0.25	1	0.70
Ashland, Wis.	1895	9,956	0.50	3	1.09
Hamilton, N. Y.	1895	1,744	0.12	1	0.03
Lambertville, N. J.	1896	4,142	0.28	2	0.25
Far Rockaway, N. Y.	1896	2,288	0.92	2	0.93
Red Bank, N. J.	1897	500	0.03	2	0.10
Somersworth, N. H.	1897	6,207	0.50	1	....
Little Falls, N. Y.	1898	8,783	0.76	1	....
Berwyn, Penna.	1898	826	0.52	3	....
Harrisburg, Penna.	1899	1,200	0.12	2	0.15
Albany, N. Y.	1899	94,923	5.60	8	11.00[54]
Rock Island, Illinois	1899	13,634	1.20	3	3.50
Total	....	259,774	17.31	45	26.87
BRITISH COLUMBIA.
Victoria	....	16,841	0.82	3	1.80
SOUTH AMERICA.
Buenos Ayres	....	500,000	4.15	3	....
Montevidio	....	....	Filters	reported	....
HOLLAND.
Amsterdam	....	555,821	10.18	12	11.20
Rotterdam	....	290,000	6.30	18	13.00
The Hague	....	191,000	2.88	6	4.20
Schiedam	....	25,300	1.33	5	0.68
Utrecht	....	140,000	0.60	....	1.40
Groningen	....	57,900	0.59	2	....
Dordrecht	....	34,100	0.56	2	1.00
Leeuwarden	....	30,700	0.31	2	....
Vlaardingen	....	....	....	....	....
Sliedrecht	....	....	....	....	....
Gorinchem	....	10,000	....	....	....
Zutphen	....	18,000	....	....	....
Leyden	....	44,200	....	....	....
Enschede	....	....	....	....	....
Middelburg	....	17,000	....	....	....
Total	....	1,414,021	22.75	47	31.48
GREAT BRITAIN.
London	....	5,030,267	125.00	120	200.00
Liverpool	....	790,000	10.92	....	26.67
Dublin	....	349,000	5.00	10	18.00
Leeds	....	420,000	6.00	8	17.99
Bradford	....	436,260	4.62	6	13.31
Leicester	....	220,005	2.50	....	4.75
York	....	72,083	2.04	6	3.00
Edinburgh	....	292,364	2.00	4	18.00
Darlington	....	43,000	1.32	7	....
Wakefield	....	36,815	1.25	....	....
Carlisle	....	40,000	0.90	....	....
Dumfries	....	17,821	0.25	....	....
Accrington	....	42,000	....	....	....
Birmingham	....	680,140	....	....	19.05
Blackburn	....	130,000	....	....	4.10
Bolton	....	250,000	....	....	6.60
Chester	....	40,000	....	....	....
Halifax	....	217,000	....	....	5.18
Hereford	....	20,000	....	....	....
Middlesborough	....	187,331	....	....	11.39
Newcastle	....	320,000	....	....	14.00
Oldham	....	145,800	....	....	5.30
Oxford	....	53,000	....	....	1.59
Preston	....	113,864	....	....	4.20
Reading	....	71,558	....	....	3.00
Southampton	....	76,430	....	....	3.45
Wigan	....	60,000	....	....	1.22
Worcester	....	45,000	....	....	1.93
Total	....	10,199,738	161.80	161	382.73
GERMANY.
Hamburg	....	661,200	42.00	22	33.00
Berlin	....	1,746,424	31.45	55	36.00
Breslau	....	380,000	5.12	5	8.20
Magdeburg	....	217,067	3.76	11	5.66
Bremen	....	157,500	3.21	12	3.50
Altona	....	162,427	3.08	13	5.40
Königsberg	....	176,000	2.70	7	3.00
Stuttgart	....	162,516	2.32	....	4.00
Stettin	....	145,000	2.26	9	3.00
Lübeck	....	70,000	1.40	6	4.50
Brunswick	....	100,883	1.48	4	2.30
Stralsund	....	30,105	1.11	6	0.60
Rostock	....	49,891	1.11	3	1.54
Lignitz	....	46,852	0.96	6	1.40
Posen	....	75,000	0.70	4	0.90
Schwerin	....	36,000	0.65	4	0.50
Chemnitz	....	164,743	0.59	3	....
Worms	....	30,000	0.50	3	0.64
Ratibor	....	20,729	0.42	3	....
Frankfort on Oder	....	59,161	0.37	5	0.89
Kiel	....	69,214	0.31	....	1.50
Tilsit	....	30,000	0.25	....	0.20
Brieg	....	20,154	0.20	4	....
Gluckstadt	....	6,214	0.14	....	0.10
Wandsbeck	....	22,000	0.13	....	0.30
Total	....	4,639,080	106.22	185	117.13
OTHER EUROPEAN FILTERS.
Warsaw	....	500,000	6.20	12	6.00
St. Petersburg	....	954,000	5.85	11	39.00
Odessa	....	380,000	4.75	5	8.00
Choisy le Roi and	....	}200,000{	3.85	25	10.00
Neuilly sur Marne	....		2.31	15	....
Copenhagen	....	340,000	2.88	9	6.80
Stockholm	....	274,000	2.78	....	7.00
Antwerp	....	240,000	2.10	8	2.00
Zürich	....	96,839	1.66	....	7.00
Brunn	....	....	1.62	....	3.04
Constantinople, South side	....	....	0.74	3	....
Total	....	2,984,839	34.74	88	88.84
ASIA.
Blandarwada, India	....	....	1.97	6	....
Agra, India	....	....	1.37	....	....
Bombay, India	....	821,000	1.22	4	....
Shanghai, China	....	....	0.88	4	....
Hong Kong	....	....	0.67	6	....
Yokohama, Japan	....	110,000	0.58	3	....
Calcutta, India	....	466,000	....	....	....
Tokyo, Japan	....	....	....	....	....
Baroda, India	....	....	....	....	....
Allahabad, India	....	....	....	....	....
Total	....	1,397,000	6.69	23
SUMMARY.
United States	....	259,774	17.31	45	26.87
British Columbia	....	16,841	0.82	3	1.80
South America	....	500,000	4.15	3	....
Holland	....	1,414,021	22.75	47	31.48
Great Britain	....	10,199,738	161.80	161	382.73
Germany	....	4,639,080	106.22	185	117.13
Other European countries	....	2,984,839	34.74	88	88.84
Asia	....	1,397,000	6.69	23	....
Total	....	21,411,293	354.48	555	648.85

LIST OF CITIES AND TOWNS USING MECHANICAL FILTERS. ARRANGED BY POPULATIONS.
Abbreviations.--P., Pressure filters; G., Gravity filters; J., Jewell system; N. Y., New York system;W., Warren system; C., Continental system; Am., American system.
Place.	Population, 1890.	Filters First Installed.	Nominal Capacity of Filters, 1899. Million Gallons.	Average Consumption, Million Gallons: Water Works Manual.	Area of Filters, Sq. Ft., 1899.	Filter System.
Denver, Col.	108,204				2260	Special.
Atlanta, Ga.	65,533	1887	8	4.54	2056	N. Y. P.
St. Joseph, Mo.	52,324	1898	10.2		3842	J. G.
Oakland, Cal.	48,682	1891	5	10	1960	N. Y. P.
Kansas City, Kan.	38,316	1898	6	2	2260	J. G.
Wilkesbarre, Pa.[55]	37,718		10		3166	J. G.
Norfolk, Va.	34,871	1899	6	3.5	2112	J. G.
Augusta, Ga.	33,300	1899	6	3.8	2112	N. Y. G.
Quincy. Ill.	30,494	1892	4	1.2	1582	J. G.
Dubuque, Iowa[56]	30,311	1899	2		880	J. G.
Terre Haute, Ind.	30,217	1890	4	3{	1076 226	N. Y. P. J. G.
Elmira, N. Y.	29,708	1897	6	3	2034	J. G.
Chattanooga, Tenn.	29,100	1887	9		2080	J. & N. Y. P.
Davenport, Iowa	26,872	1891	7.5	3	2380	Am. P.
Little Rock, Ark.	25,874	1891	5.5		1544	Am., J., & N. Y. P.
Winnipeg, Mann.	25,642	1887	1.5	390	N. Y.	P.
Oshkosh, Wis.	22,836	1891	2.4	2.1	550	W. G.
Macon, Ga.	22,746	1893	4	1.65	1437	J., W., & N. Y.
Burlington, Ia.	22,565	1894	3.5		1243	J. G.
Knoxville, Tenn.	22,535	1894	5	1.93	1404	W. G.
Lexington, Ky.	21,567	1895	2	1.2	678	J. G.
Kingston, N. Y.	21,261	1897	4	1.5	1120	N. Y. P.
York, Penna.	20,793	1899	4	2.37	1408	J. G.
Biddeford, Maine	20,500	1896	3	2	780	W. G.
Newport, R. I.	19,467		4	2.1		Special.
Bangor, Maine	19,103	1897	5	3	1404	W. G.
Cedar Rapids, Ia.	18,020	1896	2.5	2	905	J. G.
Elgin, Ill.	17,823	1888	4.3	1	780	Am. P.
Decatur, Ill.	16,841	1893	3	2	1008	W. G.
Belleville, Ill.	15,361		1	0.6	339	J. G.
Columbia, S. C.	15,353	1892	3		678	J. G.
Keokuk, Ia.	14,101	1893	3		980	N. Y. P.
Ottumwa, Ia.	14,001	1895	2	1.2	678	J. G.
Rock Island, Ill.[55]	13,634		2	3.5	452	J. G.
Raleigh, N. C.	12,678	1887	1	1	296	N. Y. P.
Shreveport, La.	11,979	1889	1		312	N. Y. P.
New Castle, Penna	11,600	1898	4	2	1408	N. Y. G.
Charlotte, N. C.	11,557	1896	1	0.5	530	N. Y. G.
Nebraska City, Neb.	11,494	1891	0.4	0.7	116	N. Y. P.
Streator, Ill.	11,414		2	1.3	100	Western & Am. P.
Hornelsville, N. Y.[56]	10,966	1899	3		700	N. Y. P.
Augusta, Maine	10,527	1887	0.6	1.6	100	W.
St. Thomas, Ont.	10,370	1891	2.5	0.6	700	N. Y. P.
Cairo, Ill.	10,324	1889	0.8	2.5	197	N. Y. P.
Alton, Ill.	10,294	1898	3	1	1056	N. Y. G.
Asheville, N. C.	10,235	1889	1	0.35	312	N. Y. P.
Greenwich, Conn.	10,131	1887	2	0.4	592	N. Y. P.
Huntington, W. Va.	10,108	1899	2		704	N. Y. G.
Beaver Falls, Pa.	9,735		2	4.5		N. Y.
Champaign, Ill.[55]	9,719			0.75		N. Y.
Chatham, Ont.	9,052	1895	1	0.4	280	N. Y. P.
Adrian, Mich.	8,756	1899	1.75	0.45	565	J. G.
Athens, Ga.	8,639	1893	1	0.45	420	W. G.
East Providence, R. I.	8,422	1899	0.5		176	J. G.
Winston, N. C.	8,018	1895	0.5	0.3	156	W. G.
Danville, Penna.	7,998	1896	1	1	226	J. G.
Clarksville, Tenn.[56]	7,924	1899	1.5	0.5	704	J. G.
Stevens Point, Wis.	7,896	1889	0.5	0.25	156	N. Y. P.
Carlisle, Pa.	7,620	1896	1.5		339	J. G.
Calais, Me.	7,290	1893	1.5	0.85	275	W. G.
Long Branch, N. J.	7,231	1888	3	1.3	904	N. Y. P.
Creston, Ia.	7,200	1891	0.5	0.3	150	J.
St. Hyacinthe, Que.	7,016	1898	1	0.84	294	J. P.
Rome, Ga.[56]	6,957	1899	1.5	1.3	528	J. G.
Westerly, R. I.	6,813	1896	1.5	0.375	396	N. Y. G.
Merrill, Wis.	6,809	1897	1		339	J. G.
Dennison, Ohio[56]	6,767	1899	1.25	1	528	J. G.
Parsons, Kan.	6,736	1894	2	0.6	452	J. G.
Waterloo, Iowa	6,674	1891	1.5	0.7	565	J. G.
Somerville, N. J.	6,417	1885	1.9	0.75	552	N. Y. P.
Athol, Mass.	6,319	1888	1.5	0.5	350	N. Y. P.
Owego, N. Y.	6,200	1887	1	0.75	234	N. Y. P.
Brunswick, Maine	6,012	1887	0.6	0.33	100	W.
Bucyrus, Ohio	5,974	1887	0.5	0.55	156	N. Y. P.
Warren, Ohio	5,973	1896	1.5	1.5	462	W. G.
Hopkinsville, Ky.	5,833	1895	0.5	0.15	140	N. Y. P.
Brainerd, Minn.	5,703	1897	0.5		156	N. Y. P.
New Brighton, Pa.	5,616	1889	0.5		156	N. Y. P.
Niagara Falls, N. Y.	5,502	1896	4.5	2.62	1019	J. G.
Durham, N. C.	5485	1893	0.9	0.7	252	W. G.
Winfield, Kan.	5184	1894	1		336	W. G.
Louisiana, Mo.	5090	1888	0.8		242	N. Y. P. & G.
Trenton, Mo.	5039	1889	0.4		128	N. Y. P.
Lorain, Ohio	4863	1896	3	1.5	1356	J. G.
Sidney, Ohio[55]	4850			0.5		N. Y.
Mexico, Mo.	4789	1889	0.3	0.4	66	N. Y. P.
Mt. Clemens, Mich.	4748	1888	1	0.6	251	N. Y. P.
Riverside, Cal.	4683	1892	0.09		20	N. Y. P.
Columbus, Miss.[56]	4559	1899	0.5	0.175	176	J. G.
Winchester, Ky.	4519	1894	0.75	0.107	152	J. P.
Salisbury, N. C.	4418	1889	0.5	0.35	156	N. Y. P.
Eufaula, Ala.	4394	1897	0.5		140	N. Y. P.
Greenville, Tex.	4330	1888	0.8	0.175	156	N. Y. P.
Exeter, N. H.	4284	1887	0.114	0.179	34	N. Y. P.
Bordentown, N. J.	4232	1890	0.5	0.5	156	N. Y. P.
Lake Forest, Ill.	4203	1892	1		168	J. P.
Henderson, N. C.	4191	1899	0.25		118	W. G.
Reading, Mass.	4088	1896	1	0.198	336	W. G.
Goldsboro, N. C.	4017	1896	0.5	0.1	156	W. G.
Rich Hill, Mo.	4008	1893	0.5	0.24	140	N. Y. P.
Mt. Pleasant, Ia.	3997	1888	0.5		156	N. Y. P.
Murphysboro, Ill.	3880	1890	0.2		60	N. Y. P.
Brandon, Manitoba	3778	1893	1	0.36	240	N. Y. P.
Danville, Ky.	3766	1894	0.5	0.1	140	N. Y. P.
Royersford, Pa.	3612	1893	1	0.08	226	J. G.
Warsaw, Ind.	3514	1896	0.5	0.5	156	N. Y. P.
Ashbury Park, N. J.	3500		2	0.5	670	C.
Keyport, N. J.	3411	1895	0.5	0.06	156	W. G.
Deseronto, Ont.	3338	1896	0.5	0.84	147	J. P.
Milledgeville, Ga.	3322	1893	0.5		156	N. Y. P.
Carlinville, Ill.	3293		0.1		38	Am. or Jackson.
Gettysburg, Pa.	3221	1894	0.3	0.075	78	W. G.
Independence, Kan.	3127	1891	0.75	0.25	129	Am. P.
LaGrange, Ga.	3090	1893	0.25		34	N. Y. P.
Paola, Kan.	2943	1887	0.25	0.45	66	N. Y. P.
Benwood, W. Va.[56]	2934	1899	1		306	J. G.
Gadsden, Ala.	2901	1887	1.325		430	N. Y. P. & G.
Lamar, Mo.	2860	1891	0.25		78	N. Y. P.
Longueuil, Que.	2757	1895	0.4	0.3	100	N. Y. P.
Washington, Mo.	2725	1888	0.2	0.075	50	N. Y. P.
Renfrew, Ont.	2611	1897	0.432		100	N. Y. P.
Oswego, Kan.	2574	1893	0.5	0.3	140	N. Y. P.
Holden, Mo.	2520	1893	0.2	0.05	100	N. Y. P.
Burlington, Kan.	2239		0.5		79	J.
Council Grove, Kan.	2211	1898	0.5	0.08	78	N. Y.
Wakefield, R. I.[56]	2170		0.15	0.25		N. Y.
Catonsville, Md.	2115	1890	0.25		78	N. Y. P.
Attica, N. Y.	1994	1896	0.4		100	N. Y. P.
Hightstown, N. J.	1875	1899	0.25	0.025	78	N. Y. G.
No. Berwick, Me.	1803	1896	0.3		78	W. G.
Dunnville, Ont.	1776	1899	0.5		140	N. Y. P.
Rogers Park, Ill.	1708	1889	0.4	0.35	100	N. Y. P.
Eatonton, Ga.	1682	1897	0.5		132	N. Y. G.
Caldwell, Kan.	1642	1890	0.5		156	N. Y. P.
LaGrange, Tex.	1626	1891	0.25		34	N. Y. P.
Richfield Springs, N. Y.	1623	1889	0.35		100	N. Y. P.
Valatie, N. Y.	1437	1894	0.15		50	N. Y.
Tunkhannock, Pa.	1253		0.1			N. Y.
Mechanics Falls, Me.	1030	1898	0.72		176	W. G.
New Bethlehem, Pa.	1026	1899	0.1		50	J. G.
Fairmount, W. Va.	1023	1898	1		280	N. Y. P.
Atlantic Highlands, N. J.	945		0.3	0.109	130	C.
Rumford Falls, Me.	898	1897	0.5		113	W. G.
Lakewood, N. J.	730	1889	0.5		156	N. Y. P.
Veazie, Me.	650	1889	1	0.1	176	W. G.
Portersville, Cal.	606	1890	0.151	0.060	34	N. Y. P.
Holmesburg, Pa.		1896	1	0.046	280	N. Y. P.
Pickering Creek, Pa.		1896	0.75		234	W. G.
Overbrook, Penna.		1895	0.25		78	W. G.
Vandergrift, Pa.		1897	0.5		156	W. G.
Frazerville, P. Q.[56]		1899	0.2		78	N. Y. G.
Arnate, Pa.		1899	0.12		50	N. Y. G.
Chihuahua, Mex.[56]		1899	1		612	J. G.
West Reading, Pa.				0.07		W. G.
Totals	1,565,881		252	108	77,806

Special filters, neither sand nor mechanical: Wilmington, Del.; Pop., 61,431; area, 10,000 sq. ft.; nominal capacity, 10 million gallons. See Eng. News, Vol. 40, p. 146.

NOTES REGARDING SAND FILTERS IN THE UNITED STATES.

Poughkeepsie, N. Y. Designed by James P. Kirkwood, built in 1872, was the earliest of its kind in the United States. It was enlarged by the Superintendent, Charles E. Fowler, in 1896. The walls of the original filters were of rubble, and in course of time developed cracks and leaked badly. The walls of the new filter are of rubble, faced with vitrified brick. The filters treat the water of the Hudson River, which is sewage-polluted and more or less muddy. Description: Jour. N. E. Water Works Assoc., Vol. 12, p. 209.

Hudson, N. Y. Designed by James P. Kirkwood, built in 1874. enlarged in 1888. The filters are open and are used for treating the Hudson River water, which is sewage-polluted and more or less muddy. Description: Eng. News, Vol. 31, p. 487.