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Mathematics at TCD 1592-1992

years of
by T. D. Spearman


The other outstanding mathematician in Trinity at the same time as Hamilton was James Mac Cullagh, who was appointed professor of mathematics in 1835 and later transferred to the chair of natural philosophy in succession to Humphrey Lloyd. Mac Cullagh is best known for his researches in optics, and particularly for his model of the aether.
Mac Cullagh's work on light propagation was much admired. It brought him the Copley medal of the Royal Society and the Cunningham medal from the Royal Irish Academy. His achievement reflected on the one hand a strong physical intuition and deep understanding of the phenomena, and on the other a remarkable mathematical talent. Mac Cullagh's real skill was as a geometer: as an effective and inspiring teacher he influenced a generation of students who in turn maintained the emphasis on geometry within the school.
He was critical of his fellow countrymen for what he saw as their lack of pride in their own country; their lack of interest in their own past, or of care for the sites and artefacts associated with that past. In a characteristically noble gesture he paid what must have been a large part of his life savings to buy the Cross of Cong, a magnificent twelth century processional cross, when this came on the market and presented it to the Royal Irish Academy in the hope that this would be the start of a major national collection, as indeed was the case.


by William Rowan Hamilton

Wrapped as we are in an o'erwhelming cloud
Of grief and horror, shake we off a while
That horror, and that grief with words beguile;
And from our full hearts breathe, though not aloud.
Our minds to God's mysterious dealings bowed,
And mourning with the Genius of the land,
Take we awhile our reverential stand,
In the dread presence of MacCullagh's shroud.

Great, good, unhappy! for his country' fame
Too hard he toiled; from too unresting brain
His arachnoean web of thought he wove.
The planet-form* he loved, the crystal's frame
Through which he taught to trace light's remulous train,+
Shall be his symbols in the cypress grove.

* The Eilipsoid. +The vibrations of the ether.

Mac Cullagh himself died tragically, by his own hand, at the age of 38. Although he was regarded with deep affection by his friends and students yet he could be introspective and lonely, insecure and prone to depression. It was in one of his periods of depression, following his unsuccessful candidature for a parliamentary seat in the university consistuency, that he committed suicide. Sonnett on the death of Professor MacCullagh. Hamilton held an exaggerated opinion of his own ability as a poet. Fortunately, Wordsworth felt it his responsibility as a friend to disabuse him, otherwise more valuable time might have been deflected from mathematics. Nevertheless this poem does reflect the author's genuine distress at MacCullagh's tragic death; it also perhaps retains the slightly patronising tone which Hamilton generally adopted towards `poor MacCullagh' and which rankled predictably with that proud spirit.

Next: The aether

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