It is important to note that all three of the new developments did not appear at exactly the same time nor did they reach all of the Basket Makers at the same time. They spread from one group to the next. They were slow in getting to some regions or, since there are conservatives among all people, perhaps some of the Basket Makers were hesitant about accepting the new-fangled contraptions. It is extremely doubtful if the Basket Makers invented a single one of the important new things. New inventions usually were passed from one tribe to another: often an intricate contrivance such as the bow and arrow traveled all over the world after a single invention. The Basket Makers did a certain amount of traveling and trading and they were not averse to borrowing new ideas from their neighbors. It seems fairly certain that pottery came to them from the south where other tribes had been making it prior to its arrival in the Mesa Verde region. Some of the Basket Maker men, while on a trading expedition, may have seen women making vessels out of clay. Realizing the superiority of these vessels which could be placed directly on the fire the men mentioned the matter to their wives upon their return home. Possessed only of the idea, the women began trying to make pottery. They were practically forced to invent pottery all over again for they knew nothing about the actual process. They had merely heard that fine vessels could be made from clay. Their first attempts were extremely clumsy and resulted in absolute failure. They made the first pots from pure clay and as fast as it dried the vessels cracked and fell into pieces. After a time the women realized they must add something to the clay to hold it together. Straw and juniper bark were tried and there was a certain measure of success. The vessels had less tendency to crack but when they were placed on the fire the straw burned out and the result was more in the nature of a sieve than a pot. The patient women continued to experiment and at last they learned that some kind of sand or grit was necessary for temper. In several places in the Mesa Verde volcanic formations provided the potters with an abundance of volcanic grit. When this was ground fine and added to the pottery clay the vessels did not crack upon drying. The first pieces of pottery were merely sun dried but soon the women learned that if they were subjected to intense heat they were much stronger and were waterproof. Each vessel was carefully baked, or fired, and true pottery was the result.