A. Veins _as small as hairs_ running _all over the body_; so called from the Latin word "capilla'ris" (_like a hair_). Q. _Do these CAPILLARY VEINS run all over the human body?_ A. Yes. Whenever blood _flows from a wound_, some _vein_ must be divided; and as you cannot insert a needle into _any part of the body without bringing blood_, therefore these little veins must run _through every part_ of the human frame. Q. _How do HYDROGEN gas and CARBON get into these very little veins?_ A. The food we eat is _converted into blood_, and blood contains both _hydrogen_ and _carbon_. Q. _How does COMBUSTION take place in the veins?_ A. The _carbon of the blood_ combines with the _oxygen of the air we breathe_, and forms into _carbonic acid gas_. Q. _What BECOMES of this CARBONIC ACID GAS formed in the human blood?_ A. Some of it is _thrown off by the breath_; and the rest of it is _absorbed by the blood_, to keep up the animal heat. Q. _What is the cause of the COMBUSTION of FIRE?_ A. The _carbon of fuel_ unites with the _oxygen of the air_, and forms _carbonic acid gas_. Q. _What is the cause of the COMBUSTION of a CANDLE or LAMP?_ A. The _carbon of the oil or tallow_ unites with the _oxygen of the air_, and forms _carbonic acid gas_. Q. _What is the cause of SPONTANEOUS COMBUSTION?_ A. The piled-up goods _ferment from heat and damp_; and (during fermentation) _carbonic acid gas is formed_, as in the two former cases. Q. _Does the HEAT of the HUMAN BODY arise from the SAME CAUSE as the heat of FIRE?_ A. Yes, precisely. The _carbon of the blood_, combining with the _oxygen of air inhaled_, produces _carbonic acid gas_, which is attended with combustion. Q. _If animal heat is produced by COMBUSTION, why does not the human body BURN UP like a coal or candle?_ A. It actually does so. Every muscle, nerve, and organ of the body, actually _wastes away like a burning candle_; and (being reduced to air and ashes) is rejected from the system as useless. Q. _If every bone, muscle, nerve, and organ, is thus consumed by combustion, why is not the BODY entirely CONSUMED?_ A. It would be so, unless the parts destroyed _were perpetually renewed_: but as a lamp will not go out, _so long as it is supplied with fresh oil_; neither will the _body_ be consumed, _so long as it is supplied with sufficient food_. Q. _When a man is STARVED, what parts of the body go first?_ A. First the _fat_, because it is the most combustible; then the _muscles_; last of all the _brain_; and then the man dies, like a _candle which is burnt out_. Q. _Why does WANT of sufficient NOURISHMENT often produce MADNESS?_ A. After the _fat and muscles_ of the body have been consumed by animal combustion, the _brain_ is next attacked; and (unless the patient dies) _madness must ensue from starvation_. Q. _Why does a man SHRINK when STARVED?_ A. A starved man shrinks _just as a fire does_, unless it be supplied with sufficient fuel.