1684. Records of the growth of plants are sometimes kept, to show the comparative warmth and congeniality of seasons to vegetation. When that is to be done, a table (fig. 299.) may be composed of horizontal lines, the distance between which shall represent space in feet or inches, and vertical lines, the distance between which shall represent time by months or days. Then supposing a plant (briony) beginning to push in the middle of March, make a mark on the lowest line in the middle of the column for that month, and trace the line as the plant grows, ascending diagonally through the other months, according to the progress of the shoot in feet. If a kidneybean germinates in the beginning of April, and attains the height of ten feet by the first of September, then the indicatory line will pass through five vertical columns or months, and through ten feet, or spaces, between the horizontal lines (as in the figure). All these books, tables, and records must be kept in the office as a part of its library; by which means, when the head gardener is changed, the new-comer will the sooner become acquainted with the situation and climate, his duties, and a variety of other useful circumstances.