A traditional windmill has a set of sails attached to an approximately horizontal windshaft, so when the wind acts upon the sails, they rotate in a vertical plane. There is one particular disadvantage to this arrangement that has occurred to multiple inventors throughout the ages - in order to work, the mill has to be made to face towards the wind direction.
So they reason, why not design a windmill where the sails rotate in the horizontal plane, (and thus around a vertical axis). As long as you can arrange it so that the wind only acts on one side of the axle, then it doesn't matter which direction it comes from - it will create a rotational force.
In fact the earliest mills were probably simple horizontal mills - as evidenced by some of the remaining Persian windmills.
Of course, nothing is that simple - as well as it being problematic to return the sails upwind after they have done their job (or equivalently to ensure that half of the area swept by the sails is blocked off from the wind), the horizontal windmill also has to support the whole of the weight of the sails on a single bearing at the base of the shaft. That bearing also has to resist the lateral forces that the the wind is causing on the structure - so there are considerable mechanical issues to be solved.
VIII. Concerning horizontal windmills and waterwheels, with oblique vanes
Observations upon the effects of common windmills, with oblique vanes, have led many to imagine, that could the vanes be brought to receive the direct impulse, like a ship sailing before the wind, it would be a very great improvement in point of power: while others attending to the extraordinary and even unexpected effects of oblique vanes have been led to imagine that oblique vanes applied to water-mills, would as much exceed the common water-wheels, as the vertical wind-mills are found to have exceeded all attempts towards an horizontal one. Both these notions, but especially the first, have so plausible an appearance that of late years there has seldom been wanting those, who having assiduously employed themselves to bring to bear designs of this kind: it may not therefore be unacceptable to endeavour to see this matter in a clear light.
... Hence we deduce this General Proposition,
That all planes, however situated, that intercept the same section of the wind, and having the same relative velocity, in regard to the wind, when reduced into the same direction, have equal powers to produce mechanical effects. For what is lost by the obliquity of the impulse, is gained by the velocity of the motion.
Hence it appears, that an oblique sail is under no disadvantage in respect of power, compared with a direct one; except what arises from a diminution of its breadth, in respect to the section of the wind: the breadth I N being by obliquity reduced to I K.
The disadvantage of horizontal windmills therefore does not consist in this; that each sail, when directly exposed to the wind is capable of a less power, than an oblique one of the same dimensions; but that in an horizontal windmill, little more than one sail can be acting at once: whereas in the common windmill, all the 4 act together: and therefore, supposing each vane of a horizontal windmill, on the same dimensions as each vane of the vertical, it is manifest the power of a vertical mill with 4 sails will be 4 times greater than the power of the horizontal one, let its number of vanes be what it will: this disadvantage arises from the nature of the thing; but if we consider the further disadvantage, that arises from the difficulty of getting the sails back again against the wind, &c. we need not wonder if this kind of mill is in reality found to have not above 1/8 or 1/10 of the power of the common sort; as has appeared in some attempts of this kind.
R. BEATSON, An essay on the comparative advantages of vertical and horizontal windmills: containing a description of an horizontal windmill and water-mill, upon a new construction, and explaining the manner of applying the same principle to pumps, sluices, methods for moving boats or vessels, &c. Tract. 8vo. vol. 22. Plates. Lond. 1798British Windmills, A Bibliographical Guide, THIRD EDITION adds a publisher (I & J Taylor 1798)
Via a footnote in A TOUR THROUGH THE ISLAND OF MAN, IN 1797 AND 1798, Letter X
Robert Beatson, Esq. has just published a treatise on the advantages of horizontal wind and water mills, with a plan of one of the latter, which moves the same way, let the current run up or down. See Beaston's Essay on Mills, 8vo. 1798, Taylor, Holborn. Mr. B. offers further information, on application (post paid) to him, at No. 15, Great Windmill street, London; or at Burnt Island, Fifeshire.
This reference gets the name wrong (but right in the paper's Bibliography!), and I suspect the date as well, but adds that a model was produced. Old Windmills in Scotland, Proceedings of the Society of Antiquaries of Scotland, 1944
In 1793John[Robert] Beatson, F.R.S.E., London, invented a horizontal windmill and published an essay on its advantages over the vertical type. A model of one was exhibited, at that time, in Burntisland.
Wikipedia notes that there were 3 almost contemporary people called Robert Beatson and that the windmill writer was the one of Kilrie who lived 1730–1805. Most web resources muddle up all the people together.
Mola alata.*** indicates an anonymous or unrecorded author, ... indicates a missing Christian name. Coloured entries indicate mills which are covered elsewhere on this page.
***, Observations sur les moulins a vent. Mem. de Paris, A.1711. Hist. p.92. Ed.Oct. A.1711, Hist. p.120.
Leonard Euler, Recherches plus exactes sur l'effet des moulins a vent. Mem. de Berlin. A.1756. p.165.
Jean Henvi Lambert, Remarques sur les moulins a vent. Ibid. A.1775. p.92.
Johann Albert Euler, Von der Bewegung ebener Flachen, wenn sie vom Winde getrieben werden, Abhandl. der Baierischen Akad, B.3. Th.2, S.3.
Leonhardus Euler, De constructione aptissima molarum alatarum, Novi Commentar. Acad, Petropolitanae. T.4. Hist. p.8. Mem. p.41.
Johann Lulofs, Wiekundige en werktuig-kundige beschouwinge der wind-molens, Verhandel, van het Maatech, te Haarlem. Deel 2. Bl.525.
... De La Gache, Petit moulin (a eau ou a vent), inventé par lui, Machines approuvées par l'Acad, des Sc. de Paris. T.4. p.37.
... Du Bost, Description d'un moulin destiné a etre mu, soit par la force du vent, soit par celle de l'eau, Mem. de Paris. A.1741. Hist. p.165. Ed. Oct. A.1741. Hist. p.226.
***, Moulin horisontal, inventé par ... Couplet. Machines appronvées par l'Acad, des Sc. de Paris, T.1. p.105
... Du Quet, Moulin horisontal, on a la Polonoise inventé par lui, Ibid. T.1. p.107.
... Gallon, Moulin horisontal, perfectionné par lui. Ibid. T.6. p.75.
***, Moulin horisontal, inventé par Claude Francois et Jeau Claude pu Bost. Ibid T.7. p.117
... Bourrier, Observation sur un moulin horisontal, Mem. de Paris. A.1762. Hist. p.190.
Thomas Gilpin, An account of a horizontal wind-mill, Transact, of the American Soc, Vol. 1. p.339.
Don Carlos Lemaur y Don Francisco Vidal, Informe sobre maquinas inventadas Molino de viento, que se mueve horizontalmente) por Don Francisco Malo de Medina. Memor. de la Soc. Econom. de Madrid. Vol.4. p.202.
... Daclin, Projet de construction d'un moulin a vent. Cinquieme Rapport des travaux de la Soc. d'Agric. du Doubs. p.245.
Carl Knutberg, Nytt pafund vid vader-quarnars inrattning at i lungt vader malningen ma kunna forrattas medelst hast-vind, Svenska Vetensk. Acad. Handl. A.1751. S.130.
Neue Erfindung die Wind-Muhlen dergestalt einzurichten, dass das Mahlen bey Wind-Stille durch eine stehende Welle, die von Pferden getrieben wird, kann verrichtet werden. Schwedische Akad, Abhandl, J.1751. S.136.
***, Observation de l'axe des moulins a vent a l'egard du vent. Mem. de Paris, A.1701. Hist, p.140. Ed.Oct. A.1701. Hist. p.175,
... Da La Hire, Description du moulin a vent, avec le calcul de l'effort du vent sur les volans ou ailes. Mem. de Paris, T.9. p.147.
John Stedman, Of the degrees and quantities of winds requisite to move the heavier kinds of wind machines. Philos. Transact. Y.1777. p.493
John Smeaton, An experimental enquiry concerning the natural powers of water and wind to turn mills and other machines, depending on a circular motion: — Part.3. On the construction and effects of windmill-sails. Ibid. Y.1759. p.100.
... Coulomb, Observations théoriques et experimentales sur l'effet des moulins a vent, et sur la figure de leurs ailes, Mem. de Paris. A.1781. Hist. p.41. Mem. p.65.
Diderich Christian Fester, Forsog til en bestemmelse af de bequemmeste og fordeelagtigste veryticale vinger ved veir muller. Nye Saml, af det Norske Selsk, Skr, B.2. S.539
Pehr Elvius, Om horizontela wader-quarms-wingar eller segel, Svenska Vetensk, Acad. Handl. A.1740. S.395. Von wagerechten Wind - Mihlen-Fliigeln oder Segeln. Schwedische Akad, Abhandl, J.1740. S.165.
Lambertus Bicker, Verhandeling over de molen-roeden, ter beandwoordinge van de Vraag: "Welke ziin'er, om te voorkomen, dat de roeden der wind moe lens niet zoo dikwiils, als gewoonliik geschiedt, bii den as breeken, en om te weeg te brengen, dat dezelfde molens met kortere roeden, dezelfde breedte van zeilen en dezelfde kragt van wind, even sterk werken, en, bii eene onvoorziene verbeffing van wind, haare snellheid uit zichzelven maatigen?" Verhandel, van het Genootsch. te Rotterdam. Deel 4. Bl. 183.
***, Proeve ter verbetering van den gewoonen molenvang en ter zamenstelling van andere werktuigen, geschikt om moles te doen stilstaan. Natuurk. Verhandel, van het Maatsch, der Wetensch. te Haarlem. Deel 1. St.3. Bl.1
... Lassise, Observation sur un moulin a vent pour labourer la terre sans boeufs ni chevaux, présenté par lui, Mem, de Paris. A.1726. Hist. p.69. Ed. Oct. A.1726. Hist. p.94. Machines approuvées par l'Acad. des Sc. de Paris. T.4. p.157
***, Beschreibung der vom Bar. v, Werneck erfundenen neuen Wind. Schneide- und Schindel - Mihle. Oekon. Nachr. der Gesellsch. in Schlesien, B.5. S.147.
... Duduit de Mezieres, Observation sur un moulin a vent, propre a tirer l'eau d'un puits. Mem. de Paris. A.1767. Hist. p.185.
Elements of technology, Jacob Bigelow, 1831
Horizontal Windmill. This name is given to those windmills which turn on a vertical axis. Various methods are employed in their construction, in most of which the wind acts by its direct impulse, as in an undershot water wheel. In the most common forms, the sails, like float-boards, present their broadside to the wind on the acting side of the wheel, but are folded up, or turned edgewise on the returning side. These wheels, however, are found to be greatly inferior to the vertical windmill, in the amount of work which they are capable of performing, and at the present day they are little used.
The vertical wind-wheel is held and revolves in the same plane, with the inclined face of every sail constantly exposed to the force of the wind throughout the whole circuit, and the velocity of its motion is thus screwed up beyond the velocity of the wind that drives it, and the number of its revolutions is increased in proportion to the obliquity of the inclined face of the sails. When the horizontal wind-wheel is compared with this kind, its disadvantages are apparent; in the first place the wind can only act upon one side, and that side receding away from the wind, while the opposite side must move directly against it; then the velocity with which the working sails move must be deducted from the velocity of the wind, and the balance is all the velocity with which the wind can impinge upon the sails. And as the sails recede all on the same level, and near the same line, those behind intercept and break the force of the wind before it strikes the sails in advance, and thus instead of intercepting the full force of a cylinder of wind equal to the whole circumference and area of the wheel like the other, the horizontal wheel only intercepts a portion of the area of one side, and even that side in a confused and broken manner. Add to all these disadvantages, the continual clanking and cracking of the sails as each one changes its face and edge alternately to the wind, in passing the two centres, also their liability to get out of order, and the reason will be sufficiently obvious why every experienced millwright condemns this method of applying the wind to drive machinery, and the horizontal wind-wheel is only used by amateurs or visionaries.
CHAPTER XXII.
THE HORIZONTAL WINDMILL.
UNLIKE horizontal watermills, which themselves were the pioneers in watermilling, horizontal windmills are a modern variation from the original model. A variety of opinions have been entertained during the last century and a half relative to the advantages of horizontal windmills, but the general view of practical millers has been adverse to them. The sailbeam is fitted in a vertical position revolving on a pivot; the four horizontal cross-bars affixed to it carrying as many sails. While the sails of an ordinary vertical windmill all remain exposed to the air as they revolve, those of a horizontal windmill, on the contrary, must be partly screened. In one form, a semicircular shield encompasses one-half of the mill, allowing two arms to be exposed to the wind and driven round, but sheltering the other two whilst returning; and in order to enable the sails to be trimmed to the wind from any direction the shield is moveable round the mill, so as always to shelter the returning sails under its lee. Sometimes, in lieu of providing a shield, the plan known as that of Beatson is adopted: the returning sails being made to turn so as to present their edges only to the wind; a variation upon this again being found in the expedient of bringing the frames, upon which the sails are stretched, to the yard, so that they are blown out or opened when the wind bears upon them, but closed when returning against it. In another variety, the sails revolve in a fixed position from whatever direction the wind may blow. In 1767 a French machinist, named Bourrier, proposed such a contrivance to the Academy des Sciences; the council receiving the idea favourably, but finally rejecting it as impracticable on the ground that the sails, being of great length, would be bent by their own weight.But a considerably more compact and ingenious device than any of the foregoing serves its purpose perfectly. The wheel, mounted on a vertical axis, and having flat vanes fitted round its circumference, is enclosed in a circular casing, which is fitted with boards fixed obliquely, or in such lines as if produced inwards would touch the circumference of the windwheel. By this arrangement, from whatever point the wind may blow it will cause the wheel to revolve in the same direction. Part of the breeze passes between the oblique ports of the casing and acts on the plates of the wheel; while part is intercepted by the plates, and either reflected inwards so as to propel the plates in the same direction, or reflected outwards so as not to act upon them in the opposite direction. Smeaton considered the available power of a horizontal mill to be one-eighth or one-tenth that of an ordinary windmill; Ferguson says, however, he formed too low an estimate, which is more correctly estimated at one-fifth of that of the ordinary windmill. In the early part of the present century premiums were offered by the Society of Arts for "the best methods of constructing horizontal wind-mills"; but the type has never been adopted by cornmillers to any appreciable extent.
In situations where the great height required for the vertical sails would be an objection, the horizontal windmill may be used, although it is stated that such a mill has not much more than 1-fourth of the force of a vertical mill.A horizontal windmill consists of a wheel or fly formed by 6 sailbeams fixed to a central axis, as shown in Fig. 2373; to these beams are attached vanes placed so that their surfaces may be divided into two unequal parts by the axis of rotation. It must be evident, that however the vanes are arranged, while some of them are receding from the wind and causing the vertical axis to rotate, other vanes, in coming up to the wind, must produce so much friction or resistance as greatly to diminish the effect. Mr. Beatson attempted to overcome this difficulty by so arranging the vanes that the whole force of the wind might act in a direct manner on the resisting side, but when acting on the other or returning side, the parts of the vanes should give way and allow the wind to pass through. For this purpose the vane frames were filled up or covered with canvas or other light material in such a way as to form small separate parts or flaps, placed so as to overlap each other a little; by which means the flaps would be close shut when the wind was acting directly upon them, and the vane would receive its whole impulse just as if it consisted of one entire piece. But when a vane comes up to the wind the spaces are all open, the wind blows through, and the vane offers but little resistance. A better plan is to enclose the fly in a fixed cylinder, or screen formed by a number of louvre boards, arranged so that in whatever direction the wind may blow it may enter between them on one side only of a vertical plane, passing through the axis of the fly. In this way the wind acts upon the oblique surfaces of the boards on one side only of the axis, while the screen prevents the wind from acting upon those vanes which are, coming round in the opposite direction.
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