Rock Islaa-d, DL, May 12.- The Mississippi river, which has been rising steadily at this point for several days, caused great damage yesterday. The water held in check by the big government dam at Moline, which is built of solid masonry, rose with the flood, until yesterday the pressure became too great for even the immense dam to support, and about 600 feet of it gave way. The water rushed down the sluice in torrents, forcing all the milis and factories along it to shut down. Among these is the government arsenal. The damage t.o the dam is stimated at $100,000. At this point the avalanche of water broke the boom of the Rook Island Lumber company, and turned loose 10,000,000 feet of logs, valued at $15,000, and carried off the warehouse of the St. Louis & St. Paul Packet company. It flooded the levee and the streets and lots for several blocks. At Davenport, across the river, the flood played havoc in portions of the city exposed to the river front. In one neighborhood thirty families were driven frorn their homes, while many of the warehouses and wholesale houses were obliged to hastily remove their goods to places of safety. The western part ot tne city is ïnundated, and much damage is threatened to milis and other mauuiacturing industries. Chicago, May 12.- Telegrams f rom St. Paul, Minn. ; Marinette, Wis. ; Des Moines and Keokuk, Ia.; Fulton, Hls., and other joints report the Mississippi and other streams out of their banks, farms and towns looded and the usual list of spring f reshet damages,submergedrailways, etc. Many famlies have been compelled to leave their ïomes, and in some places the water is five and six feet deep over what was dry land a few days ago. At St. Paul the father of waters is within a few inches of its higbest record.