THE DELIA OF THE V/.s.s/.s.s //'/•/ /.-/r/./j ;{.-,, 



to experts in otlier lines, for the work in hand pcrtiiin.s mainly 

 to aseertaininiithe <inantit.v of .snpply. its variations, and its use. 

 Tlie facts whicli have been pnt on record are tliose concerning' 

 the source and ([Uantity of water in the river, the location and 

 character of the i)ollutin.u a^Ljencies. and inferentially the decree 

 to which the sewage or waste is dijutt-d l»y the annual How of 

 the stream. 



Until state or national legislati»)n can he secnired to regulate 

 such matters, the Potomac, as in the case of all interstate stream.s, 

 must serve as a sort of sewer into which town and manufactur- 

 ing establishments empty their rehise, and this fact must h.- 

 borne in mind in all considerations of water supplv. The im- 

 provement of water supplies from this source should begin at 

 both ends — that is to say, pollution should he prevented as far 

 as possible and the water su[)ply for a city should he filtered. 

 The state of Massachusetts has set the example in this respect, 

 preventing the pollution of streams by gradually forcing towns 

 to provide suitable sand filters for sewage before allowing it to 

 discharge into certain rivers, and also by j)rovi(ling similar sand 

 filtration for the water which is to be used for municipal pur- 

 poses. The syi^tem of intermittent sand filtration has been found 

 to be efficacious not only in taking out visible particles but in 

 nitrifying and destroying the smaller organisms apparently so 

 potent in matters of public health. 



THE DELTA OF THE MISSISSIPPI RIVERA 



liy E. L. CoKTiiKiJ,. f.lv. D.-'^c. etc. 



The Mississippi delta proper extends over KM) miles by the 

 course of the river above the city of New Orleans. The niaterials 

 composing this great mass of sedimentary deposit have been 

 partly disclosed l)y numerous artesian wells which have from 

 time to time been driven for the purpose of obtaining, if jto.ssi- 

 ble, potable water. The most notable instance, and where prob- 

 ably the most careful observations were made, is the artesian 

 Avell at Lafayette square. New Orleans. .\t a depth of 1,(>42 feet 

 the tool was Ijroken and the work ended, but driltwood was 

 pumped u[) at the last foot. 



♦Abridgment of pup.-r r.ad ln-foiv tli.- (ifonniplii.-.l Section of tli- Itriti-h V.-.-'in- 

 tion for til.' Advancement of .Seiem-e, Toronto, An>tii-t ^4. IsnT. 



