木塔管。
用于将水传送到市政当局的木管“自从不奔跑的纪念以来”。罗马人几代人使用了它。它的许多英里是在伦敦几个世纪前的街道上铺设的。去年，其中一些旧管道被从街道上移走，并在良好的保存状态下发现。美国早期的水工厂是用木管分配主管建造的。纽约和费城是众所周知的例子。在纽约地铁的建造过程中，其中一些旧的木制电源被遇到并拆除。他们被发现听起来很完美。上面提到的管道是通过无聊的松木原木和用圆形锻铁带来制作的。以齿轮和腔室的形式使这两个末端，然后将一个末端驱动到另一个。 This method of manufacture required the removal of the best part of the wood, and yet the pipes have lasted for centuries. The writer removed several hundred feet of these pipes from the streets of Wilmington some ten years ago, which had been in the ground since 1812, and not only was the wood as sound as the day it was buried, but the wrought iron bands were perfect. These facts are simply mentioned in answer to the oft repeated question, "what is the durability of wood pipe.” It might well he asked "why, if wood pipe was so durable, should cast iron and steel pipe have been substituted." The answer to that question is that the old method of making a wood pipe limited its inside diameter to the diameter of the log, and thus its place in the modern water installation was necessarily very much limited.
维度。——现代生产木材的方法pipe the diameter is unlimited. The largest wood pipe known to the writer being 9 feet 6 inches in diameter, made under the direction of Mr. John Birkinbine, of Philadelphia. The quality of the materials entering into the construction of the modern wood pipe are far superior to that used in the ancient installations, The wood is cut out of the solid logs in the form of staves from 1 inch to 3 inches in thickness, and thus the best of the log is utilized, and the inspection of the staves is an easy matter both during construction and thereafter. The steel or iron bands can be properly inspected during manufacture. and their placement properly inspected. So that there is no other character of pipe, whose quality can be better known and observed than wood pipe.
