Hairs.—Human hairs must be identified and distinguished from those of the lower mammals. If the hair has been pulled out from the root, the microscope will show that the bulbous root has a concave surface which fitted over the hair papilla, or that the root is encased in a fatty sheath.
Fibres of Clothing.—Microscopically, wool fibres are coarse, curly, and striated transversely; cotton fibres appear as flattened bands twisted into spirals; linen fibres are round, jointed at frequent intervals, with small root-like filaments; silk fibres are solid, continuous, and highly glistening.
XVI.—DEATH BY SUFFOCATION
Signs and Symptoms.—There are usually three stages:
- Exaggerated respiratory activity; air hunger; anxiety; congested appearance of face; ringing in ears.
- Loss of consciousness; convulsions; relaxation of sphincters.
- Respirations feeble and gasping, and soon cease; convulsions of stretching character; heart continues to beat for three to four minutes after breathing ceases.
Post-Mortem Appearances—External.—Cadaveric lividity well marked; nose, lips, ears, finger-tips almost black in colour; appearance may be placid or, if asphyxia has been sudden, the tongue may be protruded and eyeballs prominent, with much bloody mucus escaping from mouth and nose.
Internal.—The blood is dark and remains fluid; great engorgement of venous system, right side of heart, great veins of thorax and abdomen, liver, spleen, etc. Lungs dark purple in colour; much bloody froth escapes on squeezing them; mucous lining of trachea and bronchi congested and bright red in colour; air-cells distended or ruptured; many small hæmorrhages on surface of lungs and other organs, as well as in their substance (Tardieu's spots), due to rupture of venous capillaries from increased vascular pressure.