It is impossible for us here to rehearse all the minute symptoms, each almost trifling in itself, which warn the practised physician of the approach of one of these fearful foes in time to allow him to make a defence. We can do little more than iterate the warning, that whenever, at this momentous epoch, any disquieting change appears, be it physical or mental, let not a day be lost in summoning _skilled_, _competent_ medical advice. There is, however, a train of symptoms so frequent, so insidious, so fruitful with agony of mind and body, that we shall mention them particularly. They illustrate, at once, how all-important is close observation, and how significant to the wise physician are trifles seemingly light as air. If you notice a girl of fourteen or sixteen, who, in walking, always gives one arm in preference to the other to her companion; if, in sleeping, she mostly lies on the same side; if, in sitting, she is apt to prefer a chair with a low back, and throws one arm over its back; if you perceive that she always sits with one foot a little in advance of the other; if she, on inquiry, confesses to slight, wandering pains in one side of her chest,--do not chide her for awkwardness. These are ominous portents. They mean _spinal disease_, than which a more fearful malady is hardly known to medicine. Not less stealthy is the approach of disease of the hip-joint, of white swelling of the knee, of consumption,--all curable if taken in hand at the very first, all well-nigh hopeless when they have once unmasked their real features. Apart from these general dangers, to which those of thoroughly sound constitutions are not exposed, there are disorders called functional, to which all are subject. GREEN SICKNESS. When we speak of the 'green sickness,' we mention perhaps the most common of all, and one of which every mother has heard. Doctors call it _chlorosis_, which also means _greenness_; for one of its most common and peculiar symptoms is a pale complexion with a greenish tinge. It never occurs except at or near the age of puberty, and was long supposed to be merely an impoverishment of the blood. Now, however, we have learned that it is a disease of the nervous system, and one very often confounded by physicians with other complaints. Its attack is insidious. A distaste for exertion and society, a fitful appetite, low spirits,--these are all the symptoms noticed at first. Then, one by one, come palpitation of the heart, an unhealthy complexion, irregularity, dyspepsia, depraved tastes,--such as a desire to eat slate-pencil dust, chalk, or clay,--vague pains in body and limbs, a bad temper; until the girl, after several months, is a peevish, wretched, troublesome invalid.