Stokes, George Gabriel
Stokes was born into an Anglo-Irish family that had found its vocation for a number of generations in the established Church of Ireland. His father, Gabriel Stokes, was the rector of the parish of Skreen in County Sligo. His mother, Elizabeth Haughton, was the daughter of a rector. The youngest of six children, Stokes had three brothers, all of whom took holy orders, and two sisters. He received his earliest education from his father and the parish clerk in Skreen. Stokes then attended school in Dublin before going to Bristol College in Bristol, England, to prepare to enter university. Later in life Stokes recalled that one of his teachers at Bristol, Francis William Newman, a classicist and mathematician, had influenced him profoundly. In 1837 Stokes entered Pembroke College, Cambridge, where during his second year he began to read mathematics with William Hopkins, an outstanding private tutor whose influence on Stokes probably far outweighed that of the official college teaching. When he graduated as senior wrangler and first Smith’s prizeman in 1841, Pembroke College immediately elected him to a fellowship.
Stokes became the Lucasian professor at Cambridge in 1849, rescuing the chair from the doldrums into which it had fallen, and restoring it to the eminence it had when held by Newton. Since the Lucasian chair was poorly endowed, Stokes taught at the Government School of Mines in London in the 1850’s to augment his income. He held the Lucasian chair until his death in 1903. In 1857 he married Mary Susanna, daughter of the Reverend Thomas Romney Robinson, the astronomer at Armagh Observatory in Ireland. Stokes had to relinquish his fellowship to marry, but under new regulations he held a fellowship again from 1869 to 1902. A very active member of the Cambridge Philosophical Society, he was president from 1859 to 1861. Always willing to perform administrative tasks, Stokes became a secretary for the Royal Society of London in 1854, conscientiously carrying out his duties until 1885 when he became president of the society, a post he held until 1890. The society awarded him the Copley Medal in 1893. From 1887 to 1891 he represented the University of Cambridge in Parliament at Westminster; and from 1886 to 1903 he was president of the Victoria Institute of London, a society founded in 1865 to examine the relationship between Christianity and contemporary thought, especially science. Stokes was universally honored, particularly in later life, with degrees, medals, and membership in foreign societies. He was knighted in 1889. The University of Cambridge lavishly celebrated his jubilee as Lucasian professor in 1899, and three years later Pembroke College bestowed on him its highest honor by electing him master.
Figures & Tables
Classics of Elastic Wave Theory
In this chapter, we give a brief synopsis of each of the classic papers referred to in this collection. Where relevant, we reproduce the basic equations, recast in modern notation. Supporting works also are referred to. They are listed in the “General References” section.
Table 1 is a quick outline of the key contributions of each paper reprinted in this book.
Robert Hooke, “Potentia Restitutiva, or Spring” (Oxford, 1678)
The article by Robert Hooke, “Potentia Restitutiva, or Spring,” contains the statement of the proportional relation between stress and strain universally referred to as Hooke’s law. Although the English language has evolved somewhat since 1678, the article does not require translation. Hooke describes a variety of experiments, accompanied by illustrations, confirming the stress/strain relation over a wide range of applied loads. He emphasizes the great generality of his results.
Based on his experimental work from 1660 onward, Hooke first published his law in 1676 in the form of an anagram in Latin,
which he later revealed to be “ut tensio sic vis.” Roughly translated, this means “as the force, so is the displacement” (Love, 1911; Boyce and DiPrima, 1976).
In his treatise, Hooke examined the behavior of springs, so his first casting of the equations dealt with the restoring force on a spring, for a given displacement: