A convenient way to get them is to visit the Binondo Square where there has been market for native drugs from time immemorial. The gardeners from the neighboring towns, especially those from Pasay and Singalon, regularly offer the plants for sale and will undertake to supply you with any that may not be on hand. Inasmuch as the common names of the plants lead to many mistakes and much confusion, it is indispensable to acquaint one’s self with the description of the plant and be sure that the actual product conforms in all respects to the description. For this purpose it is well to obtain flowering specimens, and bearing this fact in mind I have been careful to indicate the flowering season of each plant. By making excursions to the towns of San Mateo and Angono I have obtained an abundance of whatever I sought and at the same time have learned by talking with the mountaineers and “curanderos,” what uses they make of their plants. The “curanderos” know a great deal concerning these uses, but become very reticent as soon as they are questioned about them. Whether it is dread of ridicule or selfishness or fear that silences them, the fact remains that it is no easy matter to glean any useful facts from them. And yet by tact and friendliness one may elicit much more information from them than first impressions would lead one to hope.
Leaves should be gathered when fully developed, rejecting the old, dried and worm-eaten ones.
The best time to gather bark is one month before the period of inflorescence, when it is rich in sap. The flowers are best gathered when about half expanded. The fruit is gathered green or ripe according to the active principle sought. The seeds should always be mature.
Not all parts of the plant are equally provided with the active principle which may be localized in the root or the flower; or distinct principles may exist in different parts of the same plant. Therefore the part indicated, and only that part, should be employed.
In the root the active substance usually resides in the bark, sometimes in the parenchyma that envelopes the woody tissue and rarely in the woody tissue itself, as, for example, in “rhubarb” and “pareira brava.”
The stem bark is also a frequent seat of the active principle, of which the outer portion contains the greater amount, according to the valuable experiments of Howard.
Some plants owe their therapeutic importance to their wood, others to their leaves or flowers, and regarding the localization of the active principle in these parts we have nothing especial to indicate. The fruit, however, may have a pericarp consisting of mucilage, starch, sugar and gum, etc., while the seeds contain fatty matter, fixed or essential oils or alkaloids, as is the case with coffee and cacao. In view of these facts, we repeat that it is indispensable to use that part of each plant which I have indicated as applicable to a determined case or condition.
I earnestly hope that the physicians and pharmacists practising in the Philippines may undertake investigations and experiments regarding the therapeutic properties of the plants of my native land, and that my endeavors may have acted as a stimulus or inspiration to the loyal and earnest study of the subjects that are now awakening such interest, not only in Europe and America, but in India and Japan.
I should be pleased to receive notes, plants or reports of researches from any one interested in the subject matter of this book, and I shall consider it a pleasure, as well as a duty, to devote my forces, small as they may be, to aiding any one who may do me the honor to claim my assistance.
T. H. P. de Tavera.