I am often asked if the results one gets in this way are not misleading, since each child might differ greatly from others. One must, of course, use great caution in drawing general conclusions from a single child, but in many things all babies are alike, and one learns to perceive pretty well which are the things. Babyhood is mainly taken up with the development of the large, general racial powers; individual differences are less important than in later childhood. And the biographical method of child study has the inestimable advantage of showing the process of evolution going on, the actual unfolding of one stage out of another, and the steps by which the changes come about. No amount of comparative statistics could give this. If I should find out that a thousand babies learned to stand at an average age of forty-six weeks and two days, I should not know as much that is important about standing, as a stage in human progress, as I should after watching a single baby carefully through the whole process of achieving balance on his little soles. Yet there are not many baby biographies in existence. There are scarcely half a dozen records that are full and consecutive enough to be at all entitled to the name, and even of more fragmentary ones the number in print as separate essays is scarcely larger. A good many more, however, have been available in manuscript to students, and many mothers no doubt keep such little notebooks. These notes are often highly exact and intelligent, as far as they go (I have found this especially true of the notebooks of members of the Association of Collegiate Alumnæ), and afford important corroborations here and there to more continuous records. It was the Germans who first thought baby life worth recording, and the most complete and scientific of all the records is a German one. The first record known was published in the last century by a Professor Tiedemann--a mere slip of an essay, long completely forgotten, but resuscitated about the middle of this century, translated into French (and lately into English), and used by all students of the subject. Some of its observations we must, with our present knowledge, set down as erroneous; but it is on the whole exact and valuable, and a remarkable thing for a man to have done more than a hundred years ago. Perhaps Darwin, in 1840, was the next person to take notes of an infant’s development; but they were taken only incidentally to another study, and were not published for more than thirty years (partly in “The Expression of the Emotions in Man and Animals,” 1873, partly in a magazine article in 1877). They are scanty but important. In the interval before they were published two or three small records had been published in Germany, and at least one paper, that of M. Taine, in France.