Headden — Brown Artesian Waters of Costilla Co., Colo. 311 



with organic matter. These points in the composition and 

 deportment of this water distinguish it from the spring and 

 well waters. 



The well waters to the east of the lake are, so far as I know, 

 white waters and of fairly good quality, but the wells to the 

 west of it but not close to it yield brown waters ; those of the 

 lower flows are so rich in sodium carbonate that they are no 

 longer potable waters and but poorly adapted for boiler use 

 owing to the fact that they foam badly. I have previously 

 stated that these brown waters are characteristic of an area of 

 approximately 420 square miles, and that all of the flows 

 within this area have the same characteristics, namely, they are 

 all more or less colored and all carry sodium carbonate. The 

 flow met with at a depth of about 200 feet, in the town of 

 Mosca, is used for domestic purposes. This water is slightly 

 colored, tastes of hydrogen sulphide, and carries 22*4 grains of 

 sodium carbonate in each imperial gallon. There are no sul- 

 phates and only traces of chlorides present in this water. This 

 flow is not strong, and shows a diminution as the number of 

 wells tapping it is increased. The water from the town well, 

 which was originally something over 800 feet deep, but in 

 which the casing was subsequently pulled to the 500 or 600 foot 

 point, is strongly colored, has a decided alkaline reaction, and 

 contains 72*6 grains of fixed residue per gallon, of which over 

 90 per cent is sodium carbonate. This is probably the most 

 strongly colored water with which I have met. The mill well 

 in the same town is from 780 to 800 feet deep, cased to the 

 bottom ; the water from this well differs from the preceding 

 only in containing more sodium carbonate or total solids per 

 gallon, 102*8 grains, and in not being nearly so deeply colored. 

 The sanitary analysis of these colored brown waters presented 

 difficulties of the same nature, but much less serious than those 

 presented by the San Luis lake water. They were so serious 

 in both cases that I resorted to defecation by means of milk of 

 lime, to which they were readily amenable. 



These brown waters are wholly different in their properties 

 from the lake water, and also from other artesian water flowing 

 from wells in comparatively close proximity ; for instance, the 

 im socla well," a brown water, carried 103*0 grains per gallon ; 

 the "gas well," supposed to be on the southern limit of the 

 brown water area, carried 37*6 grains ; while the white water 

 wells, a few miles south or east, carry only 6 grains. These 

 brown waters also differ from the spring waters of the eastern 

 part of the valley, which as a rule correspond closely in their 

 character to the artesian waters of the basin. As an illustra- 

 tion of this statement we have the Washington Springs, which 

 carry 5*958 grains per gallon, and the nearest artesian well, of 

 whose water I have an analysis, carries 6*698 grains per gallon. 



