But there are more hopeful cases sometimes met with, those namely of children in whom, either from simple weakness, or from that constitutional disorder called rickets, bone formation has been backward, and the head has consequently long remained unclosed. If such children, either from the irritation of teething, or from the straining during paroxysms of hooping cough, suffer from congestion of the brain, fluid may be poured out, which, not being compressed by the too yielding skull, may in consequence enlarge it. These cases, however, may be distinguished from the other more serious ones by the date of their commencement, which is always much later than that of the other form, by the symptoms which attend them being less severe, and by the enlargement of the skull being far slighter. Still they require watching, for while with improved health the enlargement ceases, the fluid is in a measure absorbed, and the head diminishes in size, though always remaining larger than the average; brain mischief is yet more readily set up in children with such antecedents than in others. The anxiety of parents about the size or shape of their child's head after infancy has passed, is perfectly needless. When the head has once closed it always remains so. An odd shape, with an unusual protuberance of the forehead and the hind head, sometimes remain as the evidence of that condition in infancy to which I have just referred. It is, however, an evidence of mischief passed, not of mischief going on. In children too who have suffered from rickets, an affection rarely met with except among the poor in crowded cities, distortion of the limbs is often associated with a peculiar form of the skull, but in this too there is nothing to call for anxiety, still less to excite alarm. It is only a preternaturally small head and shelving forehead, which are found associated with mental deficiency; otherwise the greatest varieties of size and shape, of symmetry, or of want of it, may be associated with an equal variety of intellectual endowment, which is just as likely to be above as below the average. =Brain Disorder from Exhaustion.=--It may at first sight appear strange that before leaving the subject of congestion and inflammation of the brain, I should find it necessary to give a caution against being misled by symptoms which though in some respects similar to those of congestion or inflammation, are in reality due to an exactly opposite condition.