Red dyes are also made by the Navajos; and the Mokis possess the skill to produce several colours, one being a deep, rich blue. These processes are all too long to admit of description here.[274] The Lenapé and other Eastern Amerinds used the juice of the wild, sweet-scented crab apple to fix the dyes, while among the Mokis the liquid generally used is urine. It must have required long and careful experiment before these people acquired their knowledge of dyeing, for some of the preparations are rather intricately compounded, but here is evidence once more that the Amerind was by no means a vagabond, but was constantly at work devising and inventing. Glue they made from fish in some localities, and in others by boiling down the skin from the head of the bison or elk, or the hoofs of animals. Cement for attaching arrow-heads and for other purposes was made by combining pine gum with other substances. In all these mixtures and combinations the proportions were either guessed at or measured, never weighed, for there was no scale or balance in use, so far as now known, in North America, though certain round stones from Mexico in Madrid have been supposed to be weights. Remarkable progress had been made in many tribes in the matter of calculating time, and the Mayas and Mexicans had advanced so far that they were able to calculate the length of the year with accuracy. What implements they employed is not known, but they were probably of wood and stone, the latter of the form of the calendar stone, before mentioned. Other tribes farther north made their calculations in a less perfect way, yet they did and do keep time records. The Sun priests of the Mokis use “what may be called a calendar stick,” says Fewkes. “These sticks are about a foot and a half long, and are divided into two parts, one section being round, the other flattened on one side. The round section is girt by fifteen shallow parallel grooves, and occupies about a third of the whole length of the stick. The remaining two-thirds of the stick have a number of parallel grooves or notches cut upon the flattened surface. Five of the latter grooves, which are situated at equal distances, are deeper than the remaining, and between each pair there are four smaller parallel grooves arranged at equal distances. The space in which these grooves are cut occupies about one-half of the flat portion of the stick. The remaining half, or that more distant from the round section, is divided into two parts, which are separated by a rectangular space, in the centre of which there is a depression called the _nā-tā-l-tci_. On one side of the depression there are three notches, on the other seven.”[275] The Eastern Amerinds computed time in their own several ways, some computing twelve, others thirteen moons to the year, usually reckoning from one planting time to another. The Dakotas, Chipeways, and others reckoned by winters.