Fred Sandback's use of tautly stretched yarn to delineate structure and thus attain, in his own words, "...the volume of sculpture without the opaque mass" provides one of the most rigorous - and powerful - manifestations of the Minimalist ethos.
Sandback, who produced the first of his string sculptures in 1967, quickly achieved recognition for this work, holding two solo exhibitions in Germany the following year.
His pioneering accent on suggestive presence continues to influence artists working within the disciplines of sculpture and installation.
The inclusion of Robert Barry may surprise, but towards the end of the 1960s the artist created several string-based works which, though now largely overlooked, are even more radically reductive than Sandback's sculptures and provide fascinating additions to the Minimalist canon, as well as the history of string-based art itself.
For a 1968 group show held at the now defunct Windham College, Vermont, Barry used rope to connect two identical campus buildings: "between them was this long, big, flat open area. I decided that I would get this heavy, white, nylon rope and string (them) together."
Other works from the time are equally significant: String Piece (1968) consists of a length of string extending from floor to ceiling, while Steel Disc Suspended 1/8 Inch Above Floor (1967, above) functions exactly as described.
Despite the formal simplicity of these pieces, they are complicated by site-specific demands on their measurements and installation, instigating a symbiotic relationship with architectural space that is evident in many contemporary practices.
Eva Hesse's posthumous profile has risen enormously in recent years, and of all the artists featured here, she's certainly one of the most influential.
Yet while the pioneering nature of her work is undeniable (particularly in its use of unorthodox materials; what appears to be string in Hesse's work is often, in fact, electrical cable or cloth-covered wire), the notion that her output was stylistically isolated requires some revision; it's worth comparing her 'fibre'-based works with the contemporaneous (or even earlier) production of artists such as Lenore Tawney, for example.
This said, Hesse's revision of minimalist vocabularies into sensuous, frequently hanging forms has exerted considerable influence on subsequent generations of artists, and is particularly notable not only in much of today's string-based art, but in the work of many contemporary sculptors besides.