In the gallery there is a large organ. It is a very respectable- looking instrument, has a healthy musical interior, and is played moderately. The members of the choir, to whom several people in the bottom of the church look up periodically, as if trying to find out either what they were doing or how they were dressed, are only in embryo. They are new singers; but some of them have fair voices, and in spite of occasional irregularity in tune and time, they get along agreeably. The elements of a good choir are within them, and they have only to persevere, in order to secure excellence, saying nothing of medals, and other tokens of appreciation. The whole of the seats in the gallery, generally used by scholars, are free. St. Mary's is situated a district containing about 8,000 persons, and as they are nearly entirely of the working class sort, the congregation is naturally made up of similar materials. Including 14 militia staff men, the congregation will number, on an average, without the scholars, about 500. More people appear to come late to this church than to any other in Preston; they keep dropping in at all times--particularly in a morning--up to within twenty minutes of the finish; but they are connected with the schools, visit the church after they have done duty there, and this accounts for their lateness. The beadle of this church has the strongest, if not the longest, official wand in the town, and he is very modest, blushing occasionally, while carrying it. The first incumbent of St. Mary's was the Rev. James Parker, a relative of Councillor Parker, of Preston, who had to retire through ill health. He exchanged livings with the Rev. W. Watson, of Ellerburne, in Yorkshire, who required a more active sphere, and found it at St. Mary's. Mr. Watson afterwards found higher preferment, and went to the South of England. Then came the Rev. Robert Lamb, who worked most vigorously in the district. He is now rector of St. Paul's, Manchester. His successor was the Rev. Henry Robert Smith, who, after staying a while, retired to St. Paul's, at Grange, where he still labours. The next incumbent was the Rev. George Alker, who came to St. Mary's in December, 1857. He is still at the church; but we dare say he would be willing to leave it for a rectory, if one were offered, with 500 pounds a year. Mr. Alker is an Irishman, and is about 42 years of age. He is rather tall; is genteelly fashioned, has good features, wears an elegantly-trimmed pair of whiskers, has pompous, odorous, Pall Mall appearance, is grandiose and special, looks like a nineteenth century Numa Pompilius, would have made a spicey Pontifex Maximus, ought to have lived in Persia, where he might have worn velvet slippers and been fanned with peacock feathers, would have been a rare general director of either fire-eaters or fire worshippers; is inclined to run when he walks alone, and to be stately, slow, regal, and precise when, like Fadladeen, he is in charge of Lalla Rookh.