I believe I have already intimated that Solomon, was well versed in the science of Anatomy; that he well understood the human frame, and perhaps much better than any before him. He had in the former verse spoken of the Animal System; in this fourth verse he proceeds to notice the Natural Faculties, inward and outward. A great writer says these words form but one sentence: _The doors shall be shut in the streets_, _when the sound of the grinding is low_. This Grinding is supposed to relate to almost every part in man, which is preserved, kept up, and supported by food, and respects the alteration which that food undergoes, that it may be really transubstantiated into our flesh. These are by Physicians called digestion or concoction. By the _sound_ of the Grinding is meant some natural symptoms which are expressive of digestion, and prove that all things are right in the bodily frame, which a want of digestion would prove to the contrary. The voice of the Grinding is the natural appetite of the stomach to meat and drink, and is what we call hunger and thirst after food, with the strength and power of the stomach to retain what it receives, and nourishes the whole body. This Grinding and its voice takes in at once all the excellencies of nature, while they are in power; but, as age comes on, all the indicators of strength and concoction must be depraved, diminished, and abolished. Loss of appetite, with all its attendants, is the lowness of the voice of this Grinding; the doors of course are shut in the streets. When this is the case with a sickly, feeble, aged body, the mouth, the throat, in speaking, and the stomach in receiving food; the nostrils, and the eyes, which are called doors, these are all affected and must weaken as nature ceaseth to perform its original offices. Thus these doors are shut in the street when the Grinding is low. The Streets are the several passages of the body, which the matter of nourishment passeth through, and are the roads and highways to and from the places where the Grinding is performed. May not this expression likewise refer to the inability of the sick, feeble, and aged, to encounter with the noise and bustle of business; and to the doors and shutters shut, as a signal of the departure of some of the family; and the voice of singing, even of common cheerfulness is altered.