The Cylinder. Helmut Müller-Sievers
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The full intricacy of rotation’s transition from divine attribute to mechanical necessity cannot be recounted here. All this fragmentary overview of theories of translation and rotation has attempted to show is that motions have their history. Properly speaking, of course, only their valuation undergoes historical change, but since these motions do not “exist” unless they are forced, their metaphysical value dominates their mechanical properties until the widespread use of engines reverses this situation.47 The ubiquitous availability of convertible motion from the steam engine and the emergence of suitable transmission replace metaphysical speculation with the forced geometry of motion—with kinematics.
Still, looking back at the roles played by translation and rotation respectively, we can appreciate the irony that steam engines met a deep desire on the part of Romantic natural philosophers who had kept the cosmic dignity of rotation alive against what they perceived as the cold rationalism of straight-line mathematical physics. It is true that the intrusion of large machines into the life of the nineteenth century pushed most poets and thinkers to the side of the protesters and even Luddites, but this had to do with the steam engine as a motor—and hence as a thermodynamic polluter, in the widest sense—or with the machine as a tool that dispossessed human workers of meaningful and remunerative work. When the Romantics articulated their opposition to the motion of machines, it was to mechanisms as metaphors (or as translations, in the Latin and kinematic version): against the state as a machine, against mechanical thinking and art making, against automata insofar as they tried to imitate or supplant natural bodies and their motions and emotions.
As far as the purely kinematic impact of the new machines was concerned, there was agreement between engineers, philosophers, and artists that bringing rotation to earth and accomplishing its conversion into other forms of motion was in fact an epochal achievement. A continuous line of thinkers from Kant to Babbage to Reuleaux, and on to Lacan and Deleuze and Guattari, and an equally continuous line of poets from Kleist to Dickinson to Beckett and Wallace Stevens testify to this view. Baudelaire went so far as to see in the visualization of kinematic conversion an essential sign of modernity. His painter of modern life, like Kleist’s Herr C., delights in depicting carriages in motion because “a carriage, like a ship, derives from its movement a mysterious and complex grace which is very difficult to note down in shorthand. The pleasure which it affords the artist’s eye would seem to spring from the series of geometrical shapes which this object, already so intricate, whether it be ship or carriage, cuts swiftly and successively into space.”48
Hopefully, this metaphysical background helps to mitigate the technicality of the following parade of cylindrical objects. For their early designers, these objects retained an aura in which the drama and the conflict between the motions—even when they were frozen in the architecture of early iron bridges and glass roofs—were still palpable. Kinematics seems an abstract science to us, but it fascinated the general public in the nineteenth century. One example is the kinematic quest for a mechanism that would produce straight-line motion. The inherent inaccuracy of Watt’s four-bar linkage and the difficulties involved in predicting solutions mathematically had set off an eager quest for a linkage that would do for the straight line what the compass did for the circle. For while the drawing of a circle by means of a compass is a legitimate expansion upon the circle’s definition, the drawing of a line by means of a straight-edge ruler is vitiated by circularity: how can the straightness of the Ur-ruler be guaranteed? In 1864, Charles-Nicolas Peaucellier solved the problem but was promptly ignored. Not ten years later, James Joseph Sylvester made the straight-line linkage the subject of his lectures at the Royal Institution, where “he spoke from the same rostrum that had been occupied by Davy, Faraday, Tyndall, Maxwell, and many other notable scientists. Professor Sylvester’s subject was ‘Recent Discoveries in Mechanical Conversion of Motion.’ ”49 That this was by no means an obscure or unpopular topic can be seen from the account of a contemporary observer who described how on the occasion of the lecture he found “all the approaches to Albermarle Street [the seat of the Royal Institution] blocked by carriages.”50 In 1877, Alfred Kempe delivered his equally popular lecture on “How to Draw a Straight Line,” in which he praised linkages in general for “their great beauty.”51 The conversion of motion through (often complex) linkages seemed finally to have attained the popular and aesthetic status for which Kleist had pleaded at the beginning of the century.
PART II
Cylinders of the Nineteenth Century
CHAPTER 4
The Cylinder as Motor
Cylinders appear in the steam engine in all three of its traditional parts: there is the cylinder in which the pressure of expanding steam lifts and pushes a second, inserted cylinder, the piston; there is the transmission, which is based on “cylinder chains”; and there is the cylinder as a tool in the all-important process of rolling. In addition, the boiler, one of the many cylindrical storage devices of the time, allows for the initial generation and compression of steam.
From a kinematic point of view, the cylinder-piston assembly in the motor achieves the isolation of translational motion along the central axis; since the cylinder wraps around the piston completely, it is an instance of “pair-closure,” which Reuleaux heralded as the negentropic ideal that would overcome the “force-closure” of, say, a wheel on a straight rail. To minimize friction and wear, the piston rod must take the position of the central axis, and the piston itself must be fitted as tightly as possible into the cylinder.
In the cylinder-piston couple, as in many other mechanical devices, the cosmic—to use Reuleaux’s term for interferences of unforced motions—coincides with the practical. Why cylinders as expansion or combustion chambers, and not another shape with a central axis, like a cube? The cosmic answer is that a shape without corners allows for a more complete utilization of energy, since steam or combustible fuel (the “flame front”) expands in spherical fashion. (The same phenomenon, slowed down considerably, led the builders of silos to abandon rectangular shapes.) It is unlikely that this consideration was much on the minds of the early steam engineers, but a more practical one certainly was: cylinders can be bored by tools in continuous rotation, thereby achieving precision and uniformity and minimizing the loss of energy. One reason for the superiority of James Watt’s early engines was the accuracy with which his partner Matthew Boulton first cast and then bored his cylinders by means of machine tools that, as we will see, were crucial for the production and reproduction of cylindrical devices.1
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