One of its most remarkable effects is that of relieving the feeling of fatigue or exhaustion, whether this be produced by brain work or bodily labour. It enables the system also to bear up under an empty stomach and when the supply of food is shortened. In this way it is of signal value to the soldier in the field. Professor E.A. Parkes, all admitted authority on these matters, bears testimony to the fact that in military service it invigorates the system and is almost equally useful against both cold and heat--against cold by reason of its warmth, and against heat by its action on the skin. It appears, also, to do sway with the need for sleep, probably from its arousing the mental faculties, and the effect of a strong cup of coffee in inducing wakefulness is well known. Coffee has, moreover, a distinct action on the heart, and tends to strengthen it. The Germans are great believers in its virtues, and Vogel, one of the principal authorities on diseases of children, recommends it for them, mixed with cream, both as a food and as a tonic.
In addition to the foregoing, coffee is also employed by reason of its important medicinal virtues. In malarious countries a cup of hot strong coffee, in the early morning, is regarded as a preventive against fever and ague. It is a valuable agent in many cases of heart disease, particularly when associated with dropsy. In Bright's disease of the kidneys, where dropsy is present, it is likewise given with benefit. Strong coffee is also a well-known remedy in asthma, both in relieving the actual attack and in acting as a restorative after it is over. It frequently gives great relief in many forms of nervous headache, particularly in that variety known as migraine, in which the pain is generally limited to one side of the head. And, lastly, coffee is a valuable remedy in opium poisoning, where there is such a tendency to a fatal coma.
From the foregoing it must be evident that coffee occupies a very high position as a beverage. All that concerns its preparation, therefore, is of undoubted interest. In the first place, to obtain coffee in perfection it is indispensable that the beans be roasted at home, and not only should the roasting be done in the house, but the operation ought really to be performed immediately before the coffee is made, and the reasons thereof I shall give in speaking of the process of roasting. Many people do not care sufficiently about the perfection of coffee to go to this trouble, and are content with having their roasted coffee beans sent to them daily from their grocer. The leading establishments roast their coffee beans daily, and from them the latter may be obtained and ground in the mill at home. This, of course, though not giving the real thing, is an immense improvement on the hallowed tradition, so dear to some, of purchasing their weekly supply of,,round coffee at a time and keeping it in a tin or vessel for use as required. But, as I said before, if perfection is aimed at, the roasting must be done at home.
In the selection of the green beans care should be taxiway to see that they are nearly all of the same size, for if some are small and others large, when it comes to roasting it will be found that the small ones are done to a cinder, while the larger beans are hardly touched. The beans, too, should be perfectly dry; if moist, they should be dried in a dish by the fire or in the oven before going into the roaster. On the coffee plantations the drying of the bean is considered a most important matter when preparing them for export.
In the process of roasting, a volatile oil which gives to coffee its unique fragrance is developed. It is somewhat curious that no amount of boiling could educe this from the raw bean. This oil is exceedingly volatile, and begins to disperse and evaporate the very moment it is born. Hence, to obtain the perfection of coffee, no time should be lost in grinding and making it directly it is roasted. When the fragrant vapour of the roasted bean is first given off, it is soon followed by a peculiar noise, caused by the splitting and crackling of the external silvery greenish covering of the raw beans.