THE COPPER RIVER DELTA 31 



ing the month of September and last through the Avinter until early 

 spring. They are of such violence that it is impossible for any one 

 to cross the delta while they prevail. 



The bodv of water intervening between the flats and the ocean reefs 

 is navigable to boats drawing from three to four feet of water, and is 

 in places navigable to these only at high tide, liiy the receding tide 

 an area of about 250 square miles is completely drained, and the sur- 

 face presents one unbroken expanse of mud. The currents during 

 the rising tide are extremel}'' swift, as the ocean reef acts as a barrier 

 until the water rises over it, when it flows in with great rapidity. The 

 average temperature of the delta during the months of June, July, 

 and August was found to be about 50° F. During the naonth of Sep- 

 tember it is 10° less, accompanied by freezing weather during the 

 nights. The vegetation is very marked. On the flats are found flowers 

 and rnarsh grass; on the sand dunes are alders, berr}^ bushes, and 

 Cottonwood trees, while on the mountain side hemlock and firs grow 

 in abundance. 



From the head of the delta to where the river leaves the marsh and 

 spreads out over the mud flats it flows nearly south, is about five miles 

 wide, and consists of numerous changeable channels, varying in depth 

 from fi ve to twent}^ feet. The river breaks through the mountain range 

 about 30 miles from the coast, and is here flanked on the east side by 

 Miles Glacier and on the west b}^ Childs Glacier. In this vicinity 

 are the rapids, which form an insurmountable barrier to all kinds of 

 upstream navigation except canoes. 



The most westerly branch of the delta is known as the Alaganik 

 Slough, being the most extensivel}^ traveled and important branch of 

 the river. Its length is about 15 miles, and it varies in widtli from 

 one half mile to one mile, with depths from five to fifteen feet, de- 

 pending on the stage of the tide. This branch is a tidal stream. The 

 average tide at the lower end during the stay of Mr Ritter's party was 

 about ten feet, while at Alaganik, at the upper end, the tide Avas from 

 two to three feet. The navigation of this branch is facilitated by the 

 fact that during flood-tide the direction of the current is east, while 

 at ebl)-tide it is west. Tliis effect is felt as far as Alaganik. 



On the Coj)per River delta are two large canneries, one at Orca and 

 the other at Odiak. The fishing season begins about May and ends 

 with July. During this time each cannery turns out about 30,000 

 cases. 



J^]. D. Pkkston. 



