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bulletin of the bureau of fisheries. 
in the 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 observations are of paiticular 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 mouth of which the village stands, and is the only supply of that village. As a 
rule the water from the melting snows runs down tlie nullali as a turbulent mountain stream, taking 
up what matter it may on its way either in solution or suspension; in other 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 
imder observation; the water is snow water rather than glacier water. There are no wells in the village, 
and, owing to the slope of the ground and the natiue 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 wdth the appearance of the disease in the villages of Chitral, McCarrison 
had observed in Gilgit 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 the 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 n and a lower 
(i). The upper channel has 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 tliis 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 with drinking water, but it 
irrigates their extensive crops, serves as an open sewer, is used for the cleansing of their 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, during the winter months, at its source clear and sparkling, but at the village 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 course, much worse. 
