He was related to the famous fabulist, Jean de La Fontaine;[4] and, belonging to a theatrical family, he was involved with the theatre from an early age.

This was M. La Fontaine ... (Hall, 1845, p. 1)Richard Harte, former journalist with the New York Telegram, one-time member of the Theosophical Society Adyar (1877-1893), a former editor and regular contributor (often under the nom de guerre "D.C.K.")

A detailed description of Lafontaine's magnetization technique, translated directly from the text of the fifth (1886) edition of his L'art de magnétiser, is presented at Hart (1903), pp. 66–69.

On leaving London, he conducted “a lengthy tour of the provinces, visiting Birmingham, Manchester, Leeds, Sheffield, Nottingham, Leicester, Liverpool, Ireland and Scotland” (Gauld, 1992, p. 204).

On returning home on the evening of Saturday 20 November 1841, Braid performed his experimentum crucis; and, operating on the principle of Occam's Razor (that 'entities ought not to be multiplied beyond necessity'), and recognizing that he could diminish, rather than multiply entities, Braid made an extraordinary decision to perform a role-reversal and treat the operator-subject interaction as subject-internal, operator-guided procedure; rather than, as Lafontaine supposed, an operator-centred, subject-external procedure.

And, further, Braid's use of 'self-' or 'auto-hypnotism' (rather than 'hetero-hypnotism'), entirely by himself, on himself, and within his own home, clearly demonstrated that it had nothing whatsoever to do with the 'gaze', 'charisma', or 'magnetism' of the operator — all it needed was a subject's 'fixity of vision' on an 'object of concentration' at such a height and such a distance from the bridge of their nose that the desired 'upwards and inwards squint' was achieved.

Braid conducted a number of experiments with self-hypnotization upon himself, and, by now convinced that he had discovered the natural psycho-physiological mechanism underlying these quite genuine effects, he performed his first act of hetero-hypnotization at his own residence, before several witnesses, including Captain Thomas Brown (1785–1862) on Monday 22 November 1841 – his first hypnotic subject was Mr. J.

The following Saturday (27 November 1841), Braid delivered his first public lecture at the Manchester Athenæum, in which, among other things, he was able to demonstrate that he could replicate the effects produced by Lafontaine, without the need for any sort of physical contact between the operator and the subject.

In another of Lafontaine's (unsubstantiated from any other source) accounts in his "memoirs", he claims that, at some unspecified time several years later, he was dining in Paris with "baronet sir Richard Dennis" [sic], who introduced him to M‘Neile.

[20] Overall, Lafontaine's tour of the United Kingdom was a financial disaster; and, perhaps, largely due to the impact of M‘Neile's sermon, Lafontaine’s subsequent lecture tour of the north was a complete financial failure, and just before he returned to France, and he was forced to send a letter to a supporter in Leeds, subsequently published in the Leeds Mercury of 17 September 1842, requesting funds.

[21] Writing in 1843, John Elliotson observed that it seemed clear that Lafontaine came to England for "pecuniary" reasons, and left because he eventually "found the affair unsuccessful".

[23] "Having removed all misconceptions, foretelling of the future, explicit or implicit invocation of the devil, the use of animal magnetism is indeed merely an act of making use of physical media that are otherwise licit and hence it is not morally forbidden, provided it does not tend toward an illicit end or toward anything depraved."

— The Sacred Congregation of the Holy Office: 28 July 1847.Soon after leaving Naples, he was granted an audience with Giovanni Maria Mastai-Ferretti (1792-1878), or Pope Pius IX, in Rome on 14 November 1849.

A lethal over-dose of morphine had been administered to the young woman within a mixture that had been prepared by Louis Ladé, a trained pharmacist, and father of the physician in question.

The girl’s father, Jean-Pierre Patonier, published a pamphlet, giving precise details of the evidence that had been provided to the coroner, denouncing the failure of the justice system.