=1469. How to avoid malaria, yellow and dengue fevers.= To avoid these diseases, which are carried by mosquitoes, we screen all houses with fine wire screens and use mosquito nets on the beds. Also, under certain conditions we take daily doses of quinine in malarious regions.

We kill the mosquitoes.

To do this we must know their habits.

Mosquitoes all lay eggs in water. These hatch out as _wigglers_ or _larvae_, which have to come to the top frequently to breathe. In about twelve days or longer they turn into _tumblers_ or _pupas_, which in a few days longer come to the top when their backs split open and the mosquito comes out and flies away.

[Ill.u.s.tration: Fig. 10

_The eggs_

_The larvae_

_The pupa_

_The mosquito leaving the pupa skin_]

_The malaria mosquito_ is domestic like the chicken and lives around in houses hiding in the gra.s.s, bushes or dark corners and comes out to bite at night. When a settlement is abandoned the malaria mosquito moves away also. She rarely flies far from home and is not found much beyond 500 yards from a house. She lays her eggs in running clear water preferably, but she will accept water in hollow trees, between the leaves of lilies or air plants or in vases of flowers, or in cisterns and water b.u.t.ts.

[Ill.u.s.tration: Fig. 11

_Catching malaria_]

[Ill.u.s.tration: Fig. 12

_On Guard_

(No mosquito bites for him)]

_The yellow fever mosquito_ is domestic like the house cat. She hangs around the house and rarely flies as far as the next house even, preferring to travel on a visitor's coat. She will bite in the day time and will lay her eggs in any little collection of water in the house, the eaves trough, the water barrel, old tin cans or bottles, pitchers, vases or the refrigerator drip.

_The dengue_ mosquito is a marsh and town mosquito. She flies far and well and will breed in any sort of water, even brackish.

_To kill mosquitoes_--

Catch them in the house; empty all water from tin cans, old barrels, etc; cover with wire all cisterns and water barrels; fill in all puddles and drain off marshes; put oil on all pools and streams to choke the wrigglers; cut down gra.s.s and bushes around houses.

CHAPTER II

PERSONAL HYGIENE

=1470.= The knowledge of taking care of the body is called _Personal Hygiene_, the princ.i.p.al rules of which are as follows:

1. KEEP THE SKIN CLEAN.

2. KEEP THE BODY PROPERLY PROTECTED AGAINST THE WEATHER.

3. KEEP THE BODY PROPERLY FED.

4. KEEP THE BODY SUPPLIED WITH FRESH AIR.

5. KEEP THE BODY WELL EXERCISED WITHOUT EXHAUSTION.

6. KEEP THE BODY RESTED BY SUFFICIENT SLEEP.

7. KEEP THE BODY FREE OF WASTES.

Sanitation is the practice of the laws of Hygiene.

=1471. RULE 1. Keep the Skin clean.= A dirty body invites sickness.

Small troubles such as chafing, sore feet, saddle boils, sore eyes, felons, whitlows, earache, toothache, carbuncles, fleas, lice and ringworms, are all caused by lack of cleanliness, and they put men on sick report.

Owing to excessive perspiration a daily bath with soap is desirable in summer and in the tropics, the year around. At least a weekly bath should always be taken when possible. When not possible to bathe, take a good rub daily with a dry towel.

Keep your feet clean with soap and water and put on dry socks before sleeping at night. Soiled socks should be washed and hung up to dry over night.

Keep your finger nails trimmed short with scissors or knife. Never bite them off. Keep them cleaned and keep your hands washed, especially at meal times.

Underwear must be washed in clean water, hot when possible and when soiled change as soon as possible.

Do not bathe or wash your clothes in dirty water. Bathing in water containing much alkali (hard water) or fine sand or mud will make the skin smart or chafe easily and cause sore eyes.

The hair of the head should be kept well-trimmed.

=1472. RULE 2. Keep the body properly protected from the weather.= Clothing of the soldier is worn as a protection. Too much causes sweating and exhaustion on the march and too little causes chills and frost bite.

Be careful to reb.u.t.ton the clothing in winter time after attending to Nature's calls. Cold fingers may make you careless, but the cold is merciless and may cause a bad frost bite.

The first feeling of frost bite is numbness and the first sign is a marble whiteness. Frost attacks first the nose, ears, cheeks, fingers and toes.

Sun glare and snow blindness may be prevented by colored goggles or a handkerchief tied across the face with a small slit for the eyes or by greasing the face and eyelids and rubbing in charcoal around the eyes.

=1473. RULE 3. Keep the body properly fed.= Your company mess is sufficient for your needs and is wholesome, provided it is well chewed. Large lumps of food take a longer time to digest than small particles do, and so they tire the stomach and also cause constipation, gas and indigestion with headache.

Do not eat food left behind in strange houses or by the enemy, nor food that smells or looks badly.

If haversack rations are issued to you, do not eat them all at the first meal, but make a division for each meal. Stuffing will make you sick on a hike and later, hunger will drive you to eat things you would not touch at other times.

Before starting on the day's hike drink all the water you can and fill your canteen with water only.

Be sure your canteen does not leak.

After starting, do not drink anything until the end of the hike.

Do not eat ice or snow to quench thirst. It will make you more thirsty. Do not drink large quant.i.ties of cold spring water when heated,--it will give you a very bad bellyache.

Do not drink whiskey or beer, especially in the field. It will weaken you and favor heat exhaustion, sunstroke, frost bite and other serious troubles.

Alcohol muddles the mind and clouds thoughts, and so causes a feeling of carelessness and silliness that may ruin some military plan, or give the whole thing away to the enemy and with it the lives of yourself and your comrades.

The soldier who drinks alcohol will be among the first to fall out exhausted.