the ancient physicians were persuaded that every period of seven years effected some material alteration in the human system; thus _Solon_, although he divided life into ten stages, considered each stage as a _Septenary_;[265] so with the Canonists there are _six_ ages, but the duration of each is _seven years_, or some multiple of that number; thus, INFANTIA from _one_ to _seven_; PUERITIA from _seven_ to _fourteen_;—ADOLESCENTIA from fourteen to _twenty-eight_;[266]—JUVENTUS from _twenty-eight_ to _fifty_; (Quere, _Forty-nine_?)—ÆTAS SENILIS from _fifty_ to _seventy_;—SENECTUS from Seventy.[267]—Before we quit the conceits of the Numerists, we may state that in their notions the number _Nine_ was supposed to possess some mystic power in relation to our ages; and for this reason, superstition has attached considerable apprehension to the age of _sixty-three_, in as much as being the multiple of both the numbers so important to our existence, viz. 9 × 7[268]. This period of life has accordingly been anticipated with fear, and passed with exultation; a conceit, which has been perpetuated in our own times, under the imposing title of the _Grand Climacteric of Life_, while its antiquity is shewn by the memorable letter of AUGUSTUS to his nephew CAIUS, in which he encourages him to celebrate his nativity as he had escaped _sixty-three_. We shall now proceed to consider the SEVEN AGES of man in detail. INFANCY—_Infantia_—(from _Infari_, not able to speak) commences at birth, and terminates at the _seventh_ year. The signs by which the age of an infant may be computed, are derived from its moral as well as physical characters; and as circumstances connected with medico-judicial inquiries may render the problem of importance, we shall proceed to offer some data that may assist its solution. The feebleness and size of the infant; its epidermis yet reddish, and wrinkled; its face covered with down; its head soft, and the _fontanelles_ greatly extended; the eye but little sensible to light, and lastly the appearance of the navel, are circumstances which will at once lead the medical practitioner to the conclusion of its not being many days old; while its smiles and tears, its upright posture in the nurses arms, the thickness and whiteness of the skin, the plumpness of its thighs and buttocks, the eagerness with which its eyes seek and follow brilliant objects, its agitation on the occurrence of noisy sounds, and its eager desire for the breast, are occurrences which will, according to the force and degree of each, announce the child’s progress towards the _third_, _fourth_, or _fifth_ month. The pleasure which it testifies at the sight of its nurse, its jealousies, and other passions, the habit of carrying its fingers and different objects to its mouth, the facility and pleasure with which it chews bread, and the copious discharge of saliva, announce the approach of dentition, and assure us that the infant must be in its seventh month.