In order to prevent mistakes in the putting together of the quires a quire mark was put on each quire, sometimes on the first sheet and sometimes on the last sheet. In the 11th century catch-words were used to show the connection of the quires. The scribes took great pains with their manuscripts and ruled them carefully before writing. The lines were pricked off carefully by the use of compasses and ruled with a stylus which made a mark or crease on the vellum. This was ordinarily applied with force enough to make a raised line on the back of the page and sometimes with force enough to show through two or three pages. Later these rulings were colored with inks of brilliant hues and formed part of the decoration of the manuscript. It has been claimed that a certain manuscript, probably dating from the 13th century, shows signs of having been ruled with a lead pencil. This is very doubtful, however. The first distinct mention of lead pencils which we have is about 1565. These pencils were made of wood and strips of natural graphite. The older literary manuscripts were written entirely in capital letters without any spacing between the words. The cursive or running hand with the letters smaller and more or less connected appears in manuscripts of later date. In the older manuscripts marks were introduced to show the ends of sentences and occasionally dots were inserted to mark the separation of words where otherwise the meaning would be ambiguous. These marks, however, are not related to our modern punctuation. The tendency to separate words appears first in non-literary documents, such as legal documents or matters of record. As the tendency to separate words developed at first only the long words were separated and for a long time short words were connected with those before them as is still done in Italian. It was not until the 11th century that the custom of spacing all words became general and then only in Latin manuscripts. The correct separation of words in Greek manuscripts was never established until the manuscripts themselves were superseded by printing in the 15th century. The paragraph appears as early as the 4th century B.C. It was generally indicated, however, by a horizontal mark rather than by spacing. The indenting of the paragraph came later and was followed by the use of the larger letter, first employed to indicate the beginning of the sentences. The development of the sentence itself as a device in composition was somewhat similar to that of the paragraph.