Background
MacCullagh was born in 1809, in Landahaussy, Northern Ireland. There is little reliable biographical information concerning MacCullagh. He was the son of a poor farmer and apparently inherited some money from a wealthy grandfather.
College Green, Dublin 2, Ireland
James began his education at the school in Castledamph and then the family moved to Strabane so that he could receive a good education. To take up a study of the classics he was sent to another school, this time in Lifford. At the age of fifteen MacCullagh entered Trinity College, Dublin. His undergraduate career was one in which he received the highest grade in almost every examination he took. He graduated in 1829 and, after graduating, he entered the Fellowship examinations.
College Green, Dublin 2, Ireland
James began his education at the school in Castledamph and then the family moved to Strabane so that he could receive a good education. To take up a study of the classics he was sent to another school, this time in Lifford. At the age of fifteen MacCullagh entered Trinity College, Dublin. His undergraduate career was one in which he received the highest grade in almost every examination he took. He graduated in 1829 and, after graduating, he entered the Fellowship examinations.
Copley Medal
MacCullagh was born in 1809, in Landahaussy, Northern Ireland. There is little reliable biographical information concerning MacCullagh. He was the son of a poor farmer and apparently inherited some money from a wealthy grandfather.
James began his education at the school in Castledamph and then the family moved to Strabane so that he could receive a good education. To take up a study of the classics he was sent to another school, this time in Lifford. At the age of fifteen MacCullagh entered Trinity College, Dublin. His undergraduate career was one in which he received the highest grade in almost every examination he took. He graduated in 1829 and, after graduating, he entered the Fellowship examinations.
Not long after failing the Fellowship examination MacCullagh submitted his first papers for publication. One was a paper on giving geometrical results on conic sections, the other was on light, in particular on double refraction in which he gave a clear construction of the Fresnel wave surface. Hamilton wrote a review of these papers in 1830. Two years later MacCullagh tried again for a Fellowship but this time, after being told that his first answer to the first mathematics question was wrong he refused to answer any further questions. Not surprisingly he failed but immediately he learned this he sent a letter containing geometrical theorems on the theory of rotations to the examiners. The results were original but, unfortunately for MacCullagh, had been obtained independently by Louis Poinsot who published them in 1834.
MacCullagh did succeed in obtaining a fellowship in 1832 and he was appointed junior assistant to the mathematics professor in Dublin.
In 1833 Hamilton announced his discovery of conical refraction of light. This was a major discovery and, following Hamilton's announcement, MacCullagh published a note on conical refraction in which he claimed at least partial priority for the discovery of conical refraction.
MacCullagh was particularly cross since he knew Hamilton had studied his 1830 papers containing these theorems since Hamilton had reviewed them. Hamilton was equally cross that his priority for the discovery of conical refraction was being challenged. MacCullagh was forced to admit, what was clearly the truth, that although conical refraction could be deduced from his theorems he had only made that deduction after Hamilton had announced the discovery. MacCullagh had been close to a great discovery but had just failed to make the final step.
In 1835 MacCullagh published on crystalline refraction and reflection. Later he discovered that Franz Neumann had read a paper on the subject to the Berlin Academy in December 1835 which was published in 1837. The two theories were identical except that Franz Neumann developed the theory much further.
Although MacCullagh had priority, Franz Neumann had stolen the glory and again MacCullagh had missed out. He produced several other papers on light, the most important being in 1839 when he applied methods used by Green to study reflection and refraction of waves at a surface. Also in 1839 MacCullagh was made an honorary member of the St. Andrews Literary and Philosophical Society which had been founded by David Brewster.
In 1842 at a meeting of the British Association in Manchester, there was a discussion on the wave or particle nature of light. Later in 1842, MacCullagh was awarded the Copley medal of the Royal Society, a particularly great achievement since Bessel was among those considered for the award.
In February 1843 MacCullagh was elected a fellow of the Royal Society. Also in 1843 MacCullagh published his most important work on geometry, namely "On surfaces of the second order" which described how surfaces such as the ellipsoid could be generated. Although he produced much less work on geometry than on light, it is his work on geometry which has survived and proved in the end the more important.
On October 24, 1847, MacCullagh committed suicide in his room in Dublin, perhaps depressed by what he saw as the decline of his mathematical powers.
MacCullagh's most significant work in optics was published in the mid-to-late 1830s; his most significant work on geometry, On surfaces of the second order, was published in 1843. MacCullagh’s 1839 paper was a prototype of the techniques of mathematical physics exploited so successfully by the British in the latter half of the nineteenth century.
MacCullagh was an Irish nationalist and a strict adherent of the doctrines of the Roman Catholic church.
MacCullagh was modest and sternly moral; despite a keen relish for society. His disappointment at losing a parliamentary election, in which he had stood as a nationalist candidate, coupled with overwork, resulted in severe dyspepsia and aggravation of the earlier mental illness. He committed suicide at the age of thirty-eight.
MacCullagh never married.
