Scientific Dressing.—By dressing scientifically it is possible to minimize the effect of the heat. The heat from the sun must be kept away from the body and the heat generated by the body permitted to escape. These results can best be accomplished by having the clothes very loose fitting, so as to leave ample air space, and by having the outer clothes of a good non-conductor of heat. The cloth, of course, should be as light in weight as possible, but it is more important to have it a good non-conductor of heat and of porous weave.
Not enough attention is paid to the selection of colors for resisting the heat. Two cloths identical except in color will show a great difference in the comparative amount of heat they let through. Light shades should be chosen, but care should be taken to see that they are not glaring, so as to irritate the eye and increase the mental effect of heat.
Linen and silk are better non-conductors than wool. And the weave of a cloth has a great deal to do with the amount of heat it lets through. Smooth, hard weaves absorb much less heat than fuzzy weaves. For this reason, serge is much cooler than worsted of the same shade and weight. A mistake is often made, however, in getting serge of a dark blue. It should be of as light a color as possible; gray is much cooler than blue. A white serge is much cooler than white flannel, because it is less fuzzy.
Linen is much cooler than woolens, because it is a better non-conductor and is of more porous weave. The linen thread is rough, which causes inequalities in the weave, permitting a more thorough circulation of air. Cotton is a still better non-conductor than linen, and would be preferable for summer clothes but for the fact that it neither wears nor holds its shape so well.
Mohair is very light in weight and cool looking. As a matter of fact, however, it is a fairly good conductor of heat, is closely woven, and usually comes in dark shades. It is a woolen cloth, and any woolen has its threads woven more closely on account of the process of manufacture than linens, cotton, and silk cloths. Linen is perhaps the best material for summer wear. It is porous in weave, light in color, and of fairly light weight.
It is well to remember that the safety valve of the body in hot weather is the evaporation of perspiration, not the act of perspiring. If the hand is put in a glove, for instance, it will perspire much more than if in the open air, but it will not be as cool. It is the evaporation that is a cooling process. If the perspiration is absorbed it cannot evaporate. That is why loose fitting undergarments are cooler than tight ones. It is also the reason why cotton is cooler next to the skin than linen or silk; it absorbs moisture less freely.
Drink Plenty of Water.—Water, and a great deal of it, is desirable at any time during the summer. It should be drunk freely during the day. Lemonade also is good, the slight acid being an aid to digestion. It is best to have beverages cooled only to a moderate temperature. Ice water is not bad, but it would be preferable if it were not at so extreme a temperature. Ice is resorted to only as a convenient means of securing a palatable temperature; the system does not crave extreme cold. Water at the temperature of the air is nauseating, so ice is put into it and the other extreme secured. Sixty degrees is the ideal temperature for drinking water. If this could be conveniently obtained it would be preferred to a greater degree of cold. Not only is it less harmful to the system, but it is more satisfying and thirst-quenching. Water put in bottles and left in a refrigerator until properly chilled is the best way of preparing a summer beverage. When any beverage is sufficiently cold to cause a pain in the head or throat when drinking it the result may be harmful. Cold water poured on the wrist or head has a cooling effect and tends to reduce the ice water habit.
If one could afford it, it would be well to drink nothing but mineral water in the summer. Not only does it assure purity, but the gas is an aid to digestion and serves to render the water more palatable. This results in more of it being drunk than if it were flat water, and it is desirable to drink as much water as possible in hot weather. By mineral water I mean carbonated bottled waters intended for table use. Care should be taken that the water is only lightly impregnated with salt.
It is much safer to drink a well-known water. The water may not be bottled at the spring or it may be bottled under unsanitary conditions. In many cases mineral water is not all that it should be in cleanliness. Unless one is sure of the purity of a bottled water good hydrant water supplied through the city pipes is safer.
In traveling, however, and at summer resorts it would be well to drink nothing but mineral water of a well-known brand. Only by doing this and by being certain that the bottle has not been refilled can one be safe. The supplied on trains and in resorts frequently is not as pure as that supplied in large cities.