"Other ministers," means deacons and subdeacons, properly so-called. When a young man goes to study for the priesthood--after he has discovered that God has called him to that sacred office--he passes several years in learning what is necessary, and in fitting himself for his sacred duties. After some time he receives what is called tonsure; that is, on the day of ordination the bishop cuts a little hair from five places on his head, to show that this young man is giving himself up to God. The tonsure is a mark of the clerical state, and in Catholic countries it is made manifest by keeping a small circular spot on the crown of the head shaved perfectly clean. It reminds the cleric or priest of having dedicated himself to God, and also of the crown of thorns worn by Our Blessed Saviour. For this reason some of the holy monks shaved all the hair from their head, with the exception of a little ring, which resembles very much a wreath or crown of hair encircling the head. You often see them thus represented in holy pictures. After the young student has received the tonsure and studied for a longer time, he receives the four Minor Orders, by which he is permitted to touch the sacred vessels of the altar, and do certain things about the church which laymen have not the right to do, especially to serve Mass. After more preparation he becomes a subdeacon, and then he may wear vestments and assist the celebrant at Solemn Mass. At a Solemn Mass there are three priests in vestments. The priest standing on the platform of the altar and celebrating Mass is called the celebrant; the one who stands just behind him, generally one step lower, is called the deacon, and the one who stands behind the deacon and on the lower step is called the subdeacon. The one who directs the whole ceremony, and gives signs to the others when to stand, sit down, or kneel, is called the Master of Ceremonies.