I have a couple of questions that may well be answerable here by certain members of my former Corps. I spent the majority of my Sapper life on the admin side of things, so my nitty gritty of matters technical/engineering is mostly in the range between superficial knowledge and non-existant. And, despite many hours of internet research, I still haven't found satisfactory answers to these questions! First, a bit of background I've been pondering what the Germans call a "Schnapsidee" (= 'crazy idea', as distinct from a "Furzidee" = 'brain fart') for a couple or three years or more. It is a true Schnapsidee, I well recall that at the time it occurred to me at least half a bottle of Scotland's finest was flowing through my veins. Discussions with a somewhat technically inclined bloke, my brother-in-law, indicate that the Schnapsidee seems to have merit, but he also cannot answer some of my specific questions or point me towards the answers. Suffice to say, the time is fast approaching to put this Schnapsidee to the test and try to make the gadget a reality all of the other questions have been satisfactorily resolved. To this end, I have now invested in a MIG/MAG welder and other such paraphernalia - fancy that, learning how to weld a year before I become an OAP! Anyway, the plan is that within a few months either the world will be beating a path to my door for licenses to use a gadget that will solve many problems or the local-friendly scrap dealer will have a lucrative day the next time he drives up our strasse! The open questions basically have to do with water and air pressures and how these pressures can be exploited. A minor part of the problem is also getting my head around the Imperial and metric ways of measuring it all! I understand that 1 bar is the equivalent of 14.7 psi. So far so good. I also understand that one of the German/metric definitions of a bar is "the force required to support a column of water 10 metres high". Alles klar! So, if a force of 1 bar is the equivalent of only 14.7 pounds, this then seems to infer that the column of water is itself very thin but how thin? A couple of times I've pratted around with conversion tables and pocket calculators (no answer found on 'tinternet) and always seem to come up with around 1 mm diameter. Could this be correct? Does anyone know the answer? It certainly seems appropriate for the metric system. Let us for the moment assume that the water column is 1 mm in diameter. Would it be true to say that if the diameter was 2 mm, the water column would only rise to 5 meters, and if 4 mm then only to around 2.5 meters? If not, then what other factors need to be taken into consideration when assessing the water column height with a larger column diameter? Do diminishing returns come into play? Finally, calculations for constellation A, the starting point for the gadget, indicate that it will produce combined air and water pressures of around 5 6 bars in constellation B. May I safely assume that these can be used as multiplying factors when calculating the water column heights/diameters leaving constellation B for constellation C? Thus, a force of 5 bars in constellation B would easily raise a water column of say 12 mm in diameter to a height of around 2 metres? Luckily, pressure calculations are not involved in constellations D, E and X they have to do with velocities and rpm! Many thanks in advance for any assistance that can be given.