Until the Wreckovation of the Roman rite, today, of course, was the Vigil of S Andrew. It still is, of course, in the book of Common Prayer.
In what follows, Mr Vincent is a college tutor hosting a breakfast; I do not think he was sympathetic to the Ritualist Movement ... He is trying to be funny, but JHN is also, I suspect, making the point that all those admirably 'Catholic' directions in the Prayer Book, to which the Ritualists delightedly pointed, were obsolete.
"At this moment the door opened, and in came the manciple with the dinner paper, which Mr Vincent had formally to run his eye over. 'Watkins,' he said, giving it back to him, 'I almost think today is one of the Fasts of the Church. Go and look, Watkins, and bring me word.' The astonished manciple, who had never been sent on such a commission in his whole career before, hastened out of the room, to task his wits how best to fulfil it. The question seemed to strike the company [of undergraduates] as forcibly, for there was a sudden silence, which was succeeded by a shuffling of feet and leave-taking; as if, though they had secured their ham and mutton at breakfast, they did not like to risk their dinner. Watkins returned sooner than could have been expected. He said that Mr Vincent was right; today was 'the feast of the Apostles'. 'The Vigil of St. Peter, you mean, Watkins,' said Mr Vincent; 'I thought so. Then let us have a plain beef steak and a saddle of mutton; no Portugal onions, or current jelly; and some simple pudding, Charlotte pudding, Watkins - that will do.'"
[I don't want to make an enormous fuss about this ... I am aware that stylish Georgian writers sometimes would split an infinitive ... but S John Henry Newman in this piece misses a number of opportunities to Split, doesn't he?]