Brass and steel suspended mobile, 635 x 229 x 229 mm (25 x 9 x 9 in)
Purchased from the artist through the Lords Gallery, London (Grant-in-Aid) 1962
Kenneth Martin: A Retrospective Exhibition, Lords Gallery, London, October-November 1962 (10)
Kenneth Martin, Tate Gallery, London, May-June 1975 (7, reproduced p.61)
Tate Gallery Review 1953-63 and Report 1962-3, London 1963, p.54, reproduced
Mary Chamot, Dennis Farr and Martin Butlin, Tate Gallery: The Modern British Paintings, Drawings and Sculpture, vol.II, London 1965, p.47
Keith Roberts, ‘Current and Forthcoming Exhibitions’, Burlington Magazine, vol.117, no.868, July 1975, p.496, reproduced opposite p.499
Penelope Curtis, Modern British Sculpture from the Collection, Tate Gallery Liverpool, 1988, p.95, reproduced p.96 (mistakenly identified as Rotary Rings)
Victor Pasmore, ‘Abstract Painting and Sculpture in England’, American Abstract Artists eds., The World of Abstract Art, London 1957, p.12
Dennis Farr, British Sculpture Since 1945, London 1965, pl.20
Michael Compton, Optical and Kinetic Art, London 1967, pl.14
Mary Martin Kenneth Martin, exh. cat., Arts Council tour 1970, back cover
James Burr, ‘Round the Galleries: All Done by Numbers’, Apollo, vol.101, no.159, May 1975, p.398
Paul Overy, ‘The Work of Kenneth Martin’, Studio International, vol.189, no.975, May-June 1975, p.175
Georgina Oliver, ‘Sculpture: Kenneth Martin’, Arts Review, vol.27, no.11, 30 May 1975, front cover
Jasia Reichardt, ‘Order and Chance’, Architectural Design, vol.45, July 1975, p.450
Fenella Crichton, ‘London: Kenneth Martin at the Tate’, Art International, vol.19, no.7, Sept. 1975, p.52
James Burr, ‘Round the Galleries: the Immediacy of America’, Apollo, vol.107, no.191, Jan. 1978, p.64
Kenneth Martin: Drawings and Prints, exhibition cat., Arts Council tour 1977, [p.4]
Sandy Nairne and Nicholas Serota eds., British Sculpture in the Twentieth Century, London 1981, p.157
Kenneth Martin, Chance Order Change, Leicester 1983, [p.3], fig.1
Having adopted abstraction in 1948-9, Kenneth Martin turned to the construction of mobiles in 1951. His first attempts were the Mobile Reflectors, in which geometrical plates were suspended and balanced from rods. In 1953, he established his most characteristic form, the Screw Mobiles, of which Small Screw Mobile was one of the earliest. The geometry resulting in spiral structures is naturally occurrent in shells; it was discussed at length in the chapter on ‘The Equiangular Spiral’ in D’Arcy Thompson’s On Growth and Form, which Martin is known to have consulted. These developments were part of a broader reassessment amongst the Constructionists by which they rejected mimetic art in favour of new (predominantly geometrical) forms, materials and techniques. They were paralleled by Mary Martin, who abandoned painting for relief making, and by Victor Pasmore and Anthony Hill, who variously produced reliefs and mobiles. Naturally occurring sequences could still be the sources for such works, as is confirmed by Kenneth Martin’s contemporary account of ‘doing a mobile which is based in part upon the great wave made by the channel steamer at Newhaven’. This could well be Small Screw Mobile.
A decade after the completion of Small Screw Mobile, the artist told the Tate that it was ‘one of the first screw mobiles I made. Starting from simplest materials and elementary Kinetic principles’. It was made from thirty-four bars of flat brass wire 3/16 inch high and 1/16 inch thick (6 x 2mm). On one side these were brazed to a stainless steel rod, which was linked to a steel ring and a swivel joint to allow for rotation in hanging. The bars vary in length from 1 1/4 inches (32mm), at the ends, to 9 inches (229mm) in the middle of the range. The bottom bar was brazed to the rod at its right end, and the location of each joint was shifted progressively until the top bar was attached at its left end; the even number of elements ensured that none was attached to the rod by its central point. Rotation was achieved by staging the attachment around the rod so that each bar was set at an angle of 10º to that which preceded it, creating a clockwise spiral. The spiral - which ended with top and bottom bars almost aligned - balanced the effect of the off-centre attachment to the rod and ensured that it hung vertically. The artist has sometimes referred to the perimeter of such spirals as constituting a ‘roulette’, a mathematical term defined in the Encyclopaedia Britannica as ‘the path of a fixed point ... situated in the plane of a curve which rolls without slipping on a fixed curve or straight line.’
In his manuscript ‘On the Development of the Mobile’ of June 1955, Martin explained that his mobiles were first worked out on paper which served as a template. A later Drawing for Screw Mobile, 1972 (Tate T01700) exemplifies how this process developed. The generating principle was the drawing of an ellipse for the profile. As he wrote of a preliminary work: ‘I attempted to render the revolution of an ellipse by means of brass rod. I divided the ellipse horizontally at regular intervals, ruled lines and then cut rods the length of the lines. I set these horizontal rods at regular intervals and at regular angles along and around a vertical brass rod. The result was an elementary helix.’ Judging from the opening passage of the manuscript and from photographs of the artist’s studio, this process had been worked out with wooden helices made with dowels, but it reached a definitive form with the ‘discovery of brass strip’ used for Small Screw Mobile. Lengths could be arranged, he continued,
like radii of a simple shape rotating round the central point, which moved at a fixed speed along a vertical line and I realised that the final form, like a spiral staircase, was dictated by the angle between each strip and the width of the strip, as well as its length. ... And so with these three elements I could compose. The point became a line and the line mounted and grew and diminished until it had completed itself.
As this implies, Martin made a number of Screw Mobiles in which these variations were explored. Notable amongst them is the Screw Mobile, 1953 (collection Sheldon Williams) in which differing grades of brass were used progressively (diminishing in one of the twists) in combination with changes in the relative angle of the bars. Elsewhere, he indicated how brass provided a material solution when he wrote that ‘the constructive artist wishing to be architectural, to open the mass and to penetrate space, is faced with a different problem. For the line drawn on the plane becomes the line in space. ... Gravity has become a direct participant, and the artist is confronted by the characteristics of material in what is for him a new way’. Gravity had influenced the Mobile Reflectors, but the introduction of brass bars and of fixed joints counter-acted their imprecisions. Although he continued to make balanced works - such as Linkage, 1955 (Tate T01765) - Martin favoured the simple suspension and rotation of the Screw Mobiles.
Andrew Forge has remarked how the elements of the Screw Mobiles served ‘to create form in movement’ adding: ‘The rods sweep space as they revolve and describe a total form.’ The unitary nature of this result encouraged Paul Overy to suggest that ‘motion becomes almost indistinguishable from stillness’. For Martin, the superimposition of the bars had a cumulative effect which led to implied as well as actual movement. He noted in a lecture of November 1956 that: ‘The initial circular motion of the first horizontal rod will be repeated by all the others, a circle will, so to speak, move from one end of the rod to the other. The solid of revolution which was aimed at will appear as a wave of motion: form producing sensation.’ The idea that non-mimetic geometrical form could be expressive was central to Martin’s view of Constructivism. In 1963, drawing a comparison with the sculpture of Matisse (whose relief Backs had been acquired by the Tate not long before), he distinguished between Matisse’s ‘process of abstraction towards a purely expressive end’ and his own ‘move by a process of construction to an expressive end’. More explicitly, he had already asserted in Nine Abstract Artists that: ‘By one or a series of building processes works can be created capable of producing feeling in the beholder, not through illusion or allusion, but through direct visual action.’ He concluded that without imitating nature such works constituted analogous ‘diagrams of forces’.
Mobile and kinetic works had had a short but illustrious history. Although knowledge of the use of kinetics by the Italian Futurist Giacomo Balla and Russian Constructivist Alexander Rodchenko remained hazy in the 1950s, Naum Gabo’s creation of form through the rapid oscillation of a wire in Kinetic Construction (Standing Wave), 1919-22 (Tate T00827) was known from its inclusion in Circle. More sedate movement was used by Barbara Hepworth in Turning Forms 1950 (Marlborough School, St Albans), made for the Festival of Britain’s South Bank site; her use of motorised rotation enhanced the form of the sculpture rather than transforming it.
The dominant maker of suspended mobiles was Alexander Calder, who had made the form his own in the preceding decades. Anthony Hill had written enthusiastically about him in Broadsheet, asserting the importance of mobiles ‘in demonstrating the possibilities of volume suspended in space’. Martin was more cautious, perhaps because his own Mobile Reflectors were formally close to Calder’s. Although acknowledging that they were ‘full of delight’, Martin rejected the fantasy of Calder’s mobiles as ‘decorative weakness’. Instead, he declared of the abstract artist: ‘we must understand our vocabulary, we must limit it and at the same time push against these limitations’. Nevertheless, it is notable that in Nine Abstract Artists he had indicated that his concerns had ‘found expression in “Mobiles in a Children’s Ward”, Whittington Hospital 1953’. Little is known of this project, the context of which suggests a playfulness associated with Calder, but the artist’s son has recalled that it was at the invitation of Dr Simon Yudkin and none of the works were made specially. The limitations which Martin sought to apply in less specialised circumstances were those of geometrical and organic progression explored in earlier paintings, such as Composition, 1948 (Tate T01758); they were transferred to the mobile in the proportional relationship of the elements and their spacing. Martin’s introduction of the central rod or core maintained a control on these relationships by reducing movement to simple rotation. In Nine Abstract Artists, Alloway suggested that the differences between the two artists lay in Martin’s conjunction of a progression of the constituent elements with an awareness of the observer’s response: ‘What is important about mobiles is that they have to be apprehended temporally. The simple and logical components of Martin’s mobiles move in time with an exceptional clarity owing to their freedom from allusions to larks or flying saucers. He conveys a sense of proportionate forms fulfilling themselves in motion.’
Like the work of other Constructivists, Martin’s mobiles forged contacts with scientific and engineering disciplines. His use of helices for the Screw Mobiles in 1953 coincided with the proposed model of a double helix for the molecular structure of DNA (deoxyribonucleic acid), published by James Watson and Francis Crick in Nature in April of that year. While Martin drew attention to the structural similarity of his mobiles to spiral staircases, the reflective surface of the brass (protected on Small Screw Mobile by varnish) afforded the extension of the work into space. As he suggested of the ‘concrete object’ in ‘An Art of Environment’: ‘Its form need no longer be solid or rectangular. It can expand into and pierce space; open space and light can enter into it. It need no longer be still but can move, linking space with time’. In this process, colour, the last illusionistic device of the painter, was replaced by reflection.
While having parallels in the work of Gabo and Georges Vantongerloo, the Screw Mobiles were indelibly identified with Martin’s work from the mid-1950s. He continued to produce more complex variants, such as Screw Mobile with Black Centre (Tate T00752), into the 1970s. Small Screw Mobile was amongst a trio of his works acquired by the Tate from his solo exhibition at the Lords Gallery 1962 (along with Oscillation T00553 and Spiral Construction T00554), indicating the beginning of official recognition.
 Martin, letter, 31 Jan. 1963, Tate Gallery catalogue files.
 Martin, typescript, p.9; Tate Gallery exhibition catalogue, 1975, p.7.
 Andrew Forge, ‘Notes on the Mobiles of Kenneth Martin’, Quadrum, 3, 1957, pp.93-4.
 Mary Martin Kenneth Martin, exhibition catalogue, Arts Council tour 1970, p.17.
 ‘Invention: a lecture’, November.1956, typescript Tate Gallery Archive 7040.2, extracted in Tate Gallery exhibition catalogue, 1975, p.9.
 Martin, letter, 31 Jan. 1963, Tate Gallery cataloguing files.
 Nine Abstract Artists, 1954, pp.31-2.
 Anthony Hill, ‘Mobiles and Alexander Calder’, Broadsheet, 1, 1951, [p.6].
 ‘On the Development of the Mobile’, June 1955, typescript Tate Gallery Archive 7040.2, p.3.
 Nine Abstract Artists, 1954, p.31.
 Paul Martin, letter to the author, 16 September 1996, Tate Gallery cataloguing files.
 Alloway in Nine Abstract Artists, 1954, p.13.
 Broadsheet, 2, [p.3].