444 BULLETIN OF THE BUREAU OF FISHERIES. 



in tlie Chitral and Gilgit Valleys of north India. McCarrison had the opportunity of 

 studying endemic conditions among the inhabitants of the small villages of this remote 

 region. His observ^ations are of particular value because the people in these small 

 States of northern India are remote from commerce, communication is extremely limited, 

 many of the communities are shut off from communication even with their neighbors, 

 and the conditions which he describes represent the development of the disease under 

 almost fixed conditions. In the Chitral Valley he describes a series of villages lying 

 along the left bank of the Chitral River, each village deriving its water supply from 

 the narrow mountainous valleys at the openings in which the villages lie. 



The water supply is in all cases derived from the melting of the snows on the hills above. It comes 

 from the nullah at the moutli of which the village stands, and is the only supply of that village. As a 

 rule the water from the melting snows runs down the nullah as a turbulent mountain stream, taking 

 up what matter it may on its way either in solution or suspension; in otiier cases it percolates into the 

 soil and appears lower down in the form of a spring, as in the case of Awi. In the summer months the 

 water is invariably gray from the presence of fine sediment. There are no real glaciers in the district 

 under observation ; the water is snow water rather than glacier water. There are no wells in the village, 

 and, owing to the slope of the groimd and the nature of the soil, water does not and can not stagnate. 



The incidence of goiter in these villages varies from lo per cent to 58 per cent and 

 appears to be dependent upon the local conditions of the village and its water supply. 

 As compared with the appearance of the disease in the villages of Chitral, McCarrison 

 had observed in Cilgit a remarkable increase of the incidence of goiter in a series of 

 villages scattered along an irrigation ditch where the incidence of the disease increases 

 from above downward. 



Gilgit lies between the parallels of latitude 35° and 37° and meridians of longitude 74° and 75°. 

 It is only, however, with Gilgit proper, the capital of the district, and not with the whole of this district 

 that these observations deal. Gilgit is situated on an alluvial fan on the right bank of the Gilgit River, 

 a tributary of the Indus. This fan is roughly 10 square miles in extent and has a gentle slope from its 

 apex, in the nullah from which it derives its water supply, to tlie river. On this extensive fan eight 

 villages are situated; collectively these are known as Gilgit. The remarks which I have made as to 

 the climate and people of Chitral apply equally to Gilgit. The valley runs east and west. The height 

 of the fan above sea level is 5,105 feet. Appended is a rough diagrammatic sketch which shows clearly 

 the water supply of the different villages of the Gilgit fan. 



The water comes from a single source and is conveyed to the different villages in open kuls or chan- 

 nels. From the diagram it will be observed that there are two main channels, an upper u and a lower 

 (i). The upper channel hiis no villages on its banks till it joins the lower kul, at the village of Majin- 

 pharri, marked (3). All these seven villages are situated on the banks of this lower kul or are supplied 

 by lesser channels branching from it. Each village in this way receives the drainings of the village 

 or villages above it, till at the last village, Kashrote, the drinking water has been polluted by the six 

 villages above. 



The water in these open channels not only supplies the inhabitants witli drinking water, but it 

 irrigates their extensive crops, serves as an open sewer, is used for the cleansing of tlieir bodies, house- 

 hold utensils, and wearing apparel. It can readily be imagined, therefore, that considerable organic 

 impurities find their way down to the lower villages; yet, being fed as these channels are by a purer 

 supply, little organic impurity can be detected by qualitative tests. 



The water is, dtu-ing the winter months, at its source clear and sparkling, but at tlie \'illage of 

 Kashrote (see diagrammatic sketch of water supply and plate Gilgit Valley, western end) invariably 

 gray from the presence of fine sediment and impurities from the villages and lands irrigated by it. 

 During the summer months when the snows are melting it is, of coiu-se, much worse. 



