(a) _The Feather Test._—In this test a feather is held to the nostrils to observe whether it moves. The feather being so light, the slightest respiration of the lung would be apt to move it. (b) _The Mirror Test._—In this test a mirror is held to the mouth and nostrils. If moisture collects on the mirror it is evident that respiratory movements are going on. If there is an absence of moisture we are quite safe in saying that the patient is dead. (c) _The Bandage Test._—In this test a bandage is placed around the arm and then twisted very tightly. If there is the slightest circulation existing in the body the blood will accumulate back of the bandage in the venous system and thus demonstrate the fact. There will also be no swelling or discoloration beyond the ligature. (d) By placing the ear to the chest over the heart, no sounds will be heard. (e) If the ear is applied over the lungs, no sounds will be heard. (f) If a cup of water is placed on the chest there will be no movement of rays or ripples on the surface. (g) If the skin is cut, no blood will flow, nor will the wound close. (h) If heat, say for instance a burning match be applied to the skin it will not blister, or if ammonia is hypodermically injected under the skin there will be no redness, but rather the skin will turn to a yellowish color. (i) The living hand when held to the light shows pink through the inner edges of the fingers, but with the dead hand it shows opaqueness. (j) When a strong light is brought before the eye the pupil of the eye will not dilate or contract. (2) The expert tests are those which a doctor or coroner might use to ascertain the fact of death. These tests are made with the stethoscope and the ophthalmoscope. (a) By the use of the stethoscope the physician can hear the sounds of the heart and if there is the slightest sound he can detect it. In the absence of any sound the body is pronounced dead. (b) By the use of the ophthalmoscope the physician is enabled to look into the pupil of the eye and if there is life he can see the blood circulating through the tiny capillaries of the retina. If he does not see this capillary circulation he is quite safe in saying the body is dead. (c) Another method consists in the hypodermic or intravenous injection of certain substances, and ascertaining whether these substances have been dispersed throughout the body. If they have, then a circulation exists and life continues, although the pulsation of the heart may not be detected by auscultation. Among the substances recommended for injection are fluorescin, sodium iodide, lithium iodide and potassium ferro-cyanide. The injection of the small quantities as used will not cause death should the patient still be living.