Schauberger
[6] In regard to the carrying capacity of wooden pipes, the following passage from a book 'The Australian Wood Pipe Company' (p. 21, publ. circa 1910) provides interesting insights. "It is conceded that smoothly-planed timber has the lowest coefficient of friction of all materials ordinarily employed for conveying water. Many extensive experiments have been made on the flow of water in various kinds of pipe operating under many conditions. Within the last few years, the United States Department of Agriculture has carried on a very extensive series of experiments on the flow of water in Wood-Stave Pipe, and attention is called to their Bulletin No. 376, and in particular to the conclusions therein: Conclusions. 'That the data now existing does not show that the Capacity of Wood-Stave pipe either increases or decreases with age. That wood pipe will convey about 15 per cent more water than a ten-year-old cast iron pipe or a new riveted pipe, and about 25 per cent more than a cast iron pipe 20 years old, or a riveted pipe ten years old.' The conclusion of Government experiments, as given above, definitely prove that the carrying capacity of Wood-Stave Pipe is from 15 percent to 25 per cent greater than metal pipe, with the additional advantage that Wood-Stave Pipe will remain smooth and clean internally throughout its entire life."- Ed. [The Energy Evolution - Harnessing Free Energy from Nature, The Transport of Ore in Double-Spiral-Flow Pipes]

"If the abusive debasement of the psyche of water is to be avoided, then it is essential that the material selected for the supply pipe is not only a poor conductor of heat, but is also of a properly-formed organic nature. The capillary is the best model of an ideal water-conduit for the proper conduction and treatment of water in terms of its material composition, internal configuration and associated functions. The most suitable material is good, healthy wood. Artificial stone (such as concrete) on the other hand is almost as unsuitable as metal for the manufacture of conduits, because only materials of natural origin should be used for the conduction of the Earth's blood. To those who protest that wood is unsuitable for the reticulation system of a city because of its limited durability, it should be pointed out that good, properly-treated wood can actually last far longer than iron.
Circumstances permitting, and apart from any other special treatment, these pipes should be laid and surrounded by sandy, humus- free bedding material in order to avoid external destructive influences to which pipes laid in the ground are frequently subjected. The poor thermal conductivity of wooden pipe-walls inhibits influences detrimental to the water's inner metabolic processes. This considerably weakens dissociations that take place under a negative temperature-gradient and at the same time retains the quality of the flowing water.
The hydraulic efficiency of pipes constructed with wooden staves is actually somewhat greater than that of iron or concrete pipes. The frequently-cited fact that wooden pipelines are cheaper to install should also not be underestimated. In any event, as must be emphasized here, the types of timber currently cultivated by modern forestry are well nigh useless for this purpose: almost without exception today's artificial plantation forests furnish timbers that possess neither the properties nor the durability of timber grown under natural conditions. It is rare today to find forests in which humanity, as forester, has not interfered destructively. Yet there are still sufficient remote stands of valuable timber untouched by contemporary forestry, to which the greatest attention must be paid if humanity is once more to be supplied with good, healthy water. Once a suitable timber has been selected pipes can then be manufactured which largely correspond to the necessary requirements.
Water can only conserve its pipe system, however, if its inner conformities with natural law are taken into account. These inner conformities prevail if the substances the water secretes, which serve to maintain and build it up, are able to fulfill their respective purposes. It need hardly be emphasized that the quality of the remaining sources of food will inevitably decline with the general deterioration of the water.
The capillaries in animal or vegetable bodies serve for the transport of blood or sap, and for the simultaneous and continuous build-up and maintenance of the capillaries themselves. Hence drinking water supply-pipes must be constructed accordingly, otherwise unwelcome processes will occur which lead to the destruction of the capillaries in the pipe-walls and to unwholesome metabolic processes in the water itself. These subsequently have the most detrimental effect imaginable on the human organism and on other bodies." [Our Senseless Toil, pages 34-35]