匹兹堡过滤记录。
在宾夕法尼亚州匹兹堡进行了详尽的测试之后，自从安装过滤系统以来，宾夕法尼亚州的水局进行了详尽的测试，最终表明伤寒率以显着的速度下降，并引用了警察查尔斯·芬利（Charles Finley）的看法。Pittsburgh’s water supply in purity now equals that served in any city of its size. In 1906, the Pittsburgh death rate from typhoid was 109.7 to the 100,000 population. In 1915 it had been decreased to 6.4 per 100,000. Non-inhabitants, or those who contract the disease outside the city, are not included in these figures, but the low rate does include those in the city who contracted typhoid from other sources than the city water supply. The water bureau has traced almost every death from the disease to local contamination. For instance, last year the source of 15 cases in one part of the city was traced to a dairy, in which the dairyman had used a spring which was infected by a leaking sewer 200 yards away, in which to wash his milk cans. Complaint that the plumbing is affected by chemicals used in the filtration process is pronounced baseless by Superintendent Finley, who says: “The water we deliver is as chemically pure as when we receive it from the river. Of course, all water carries chemicals, due to minerals in solution, but the Allegheny river is as near free from this condition as any stream in the country. There is nothing in the water supply that is more detrimental than the ordinary effect of water upon metals.” Three reasons are assigned by Mr. Finley for defective plumbing. Qne, the condition being due to old plumbing; a second, due to the removal of a crust formed by the impure water of former years on the inside of plumbing, which has gradually been removed by the clean water; and third, to a poor quality of pipe, which is susceptible to a galvanic action which disintegrates the parts forming the metal. The only chemical used in the filtration process, according to Superintendent Finley, is liquid chlorine, which is injected into the supply after filtration. One pound of the chemical is used to each 8,000,000 pounds of water. To prevent any trace of it entering the supply, three tests are made daily to determine if particles of free chlorine exist in the supply. After these tests, the water still has two days in storage before entering the supply pipes. Formerly calcium hypochlorite, a compound containing chlorine in the same proportion to the water as now used, was applied to sterilize, but the war made the compound difficult to purchase.
在宾夕法尼亚州匹兹堡进行了详尽的测试之后，自从安装过滤系统以来，宾夕法尼亚州的水局进行了详尽的测试，最终表明伤寒率以显着的速度下降，并引用了警察查尔斯·芬利（Charles Finley）的看法。Pittsburgh’s water supply in purity now equals that served in any city of its size. In 1906, the Pittsburgh death rate from typhoid was 109.7 to the 100,000 population. In 1915 it had been decreased to 6.4 per 100,000. Non-inhabitants, or those who contract the disease outside the city, are not included in these figures, but the low rate does include those in the city who contracted typhoid from other sources than the city water supply. The water bureau has traced almost every death from the disease to local contamination. For instance, last year the source of 15 cases in one part of the city was traced to a dairy, in which the dairyman had used a spring which was infected by a leaking sewer 200 yards away, in which to wash his milk cans. Complaint that the plumbing is affected by chemicals used in the filtration process is pronounced baseless by Superintendent Finley, who says: “The water we deliver is as chemically pure as when we receive it from the river. Of course, all water carries chemicals, due to minerals in solution, but the Allegheny river is as near free from this condition as any stream in the country. There is nothing in the water supply that is more detrimental than the ordinary effect of water upon metals.” Three reasons are assigned by Mr. Finley for defective plumbing. Qne, the condition being due to old plumbing; a second, due to the removal of a crust formed by the impure water of former years on the inside of plumbing, which has gradually been removed by the clean water; and third, to a poor quality of pipe, which is susceptible to a galvanic action which disintegrates the parts forming the metal. The only chemical used in the filtration process, according to Superintendent Finley, is liquid chlorine, which is injected into the supply after filtration. One pound of the chemical is used to each 8,000,000 pounds of water. To prevent any trace of it entering the supply, three tests are made daily to determine if particles of free chlorine exist in the supply. After these tests, the water still has two days in storage before entering the supply pipes. Formerly calcium hypochlorite, a compound containing chlorine in the same proportion to the water as now used, was applied to sterilize, but the war made the compound difficult to purchase.
