They had no churches, but held religious services in the open under the oak trees. They piled boulders on top of each other to form altars, or built large circular enclosures of huge flat rocks, inside of which they gathered for worship, or to assist at some ceremonial in which sacrifices of animals and occasionally of human beings were made. These human sacrifices occurred once a year at the Spring Festival which was celebrated in much the same fashion as in Greece. These masses of stone are found not only in the British Isles, the most famous of which is Stonehenge (which was recently bought by an American), but there are also many of these so-called _cromlechs_ and _menhirs_ in Brittany. It is curious how often men and women do the same things at times and places so completely separated that they could not have been influenced by each other, but did what was natural for them. It seems that between the state of being primitive or savage and of being cultured, mankind must pass through certain states of mind and certain bodily actions common to all men. In tracing the growth of any habits and actions of people,—in government, religion, amusements, art, music, manners and customs, and language, we find the same customs constantly repeated among different races. If you remember this point, you will be interested to watch, in this book, the difference between these experiences common to all mankind and those which later on, were caused by the influence that one race had on another through meeting, through conquest and through neighborly contact. The bards belonged to the priesthood and were Druids. They sang in verse the brave deeds of their countrymen, praises of the gods and heroes, and legends of war and adventure, accompanying themselves on primitive harps, or on an instrument something like the violin without a neck, called a _crwth_. They wore long robes and when they were acting as priests, these were covered with white surplices somewhat like the gowns of our own clergy. From a bit of information handed down by the bards, we learn that in Ireland, the graduate bard wore six colors in his robes, said to be the origin of the plaid of the Scotch Highlanders; the king wore seven colors; lords and ladies, five; governors of fortresses, four; officers and gentlemen, three; soldiers, two, and the people were allowed to wear only one. Even their dress seemed important and marked the rank! There were three kinds of bards: priestly bards who took part in the religious rituals and were also the historians, domestic bards who made music in honor of their masters, and heraldic bards whose duties were to arouse patriotism through songs in praise of their national heroes. They had to pass examinations to become bards, and the lower ranks were tested for knowledge and ability before being promoted to the higher ranks. Recently there has been a revival in Wales of the _Eisteddfod_, or song contests of the Druids.