During the late seventeenth century in France, the viol was beginning to emerge as one of the most important musical instruments of the day. French luthiers had created the quintessential French viol, which allowed violists in France to make their mark on viol playing, both as performers and teachers. So fervent was this enterprise that players soon formed cliques, creating two opposing schools of viol playing. One of the main protagonists who is the focus of this thesis, De Machy, led one of these schools. Although we are fully aware of this historical dichotomy, it is widely assumed that De Machy's rivals were the eventual victors of this conflict, and thus have become the model for modern violists to emulate. This has, however, encouraged modern violists to completely disregard the efforts of De Machy, which, as this thesis shall demonstrate, are as important as those of his contemporaries. Chapter 1 discusses De Machy's place in modern scholarship, giving readers an overall view of the kinds of biases and prejudices that currently exist. It also serves to act as a brief collation and analysis of modern writings that discuss De Machy. Chapter 2 provides us with a historical account of the viol in France, giving special emphasis to solo viol playing. It also traces the evolution of musical style and playing technique as well as the development of the instrument within its social role. Chapter 3 discusses French ornamentation on plucked instruments, keyboard instruments and the viol, giving special emphasis to De Machy's own ideas on ornamentation. Possible explanations for the proper execution of these ornaments are also provided. Chapter 4 revaluates Rousseau and the Traité de la Viole (1687), and seeks to determine its reliability as a credible source of information. Chapter 5 describes and analyses the quarrel between De Machy and Rousseau as described by Rousseau in the Réponce de Monsieur Rousseau (1688). In addition to providing a more complete picture of the social interactions of the viol community of the late seventeenth century, this chapter seeks to better explain the issues that De Machy and Rousseau argued about. Chapter 6 examines historical and modern writings and attempts to explain one of the main issues of aforementioned quarrel, the left hand position otherwise known as the ports de main as advocated by De Machy. Appendix A reproduces the avertissement from De Machy's Pièces de Violle. The facsimile of the original publication is presented alongside the English translation. This document is central to many of the issues discussed in this thesis. Appendix B is an English translation of the Réponce de Monsieur Rousseau. One of the aims of this thesis is to re-examine the history of the viol in France, and more specifically, its use as a solo instrument. It is through De Machy's Pièces de Violle and Rousseau's Réponce that most of this information is centred.