Traditional medicine: the sources
A herbal is a collection of plants with an educational purpose; it may be drawn (hortus pictus), dried (hortus siccus) or living (hortus vivus).
From Classical antiquity to the premodern era herbals were the best source of botanical and medical information for apothecaries and herbalists. Herbals were books containing descriptions of vegetal species and their properties, as well as their illustrations.
The most important illustrated herbal from antiquity seems to be the one produced for Princess Anicia Juliana in the sixth century AD, followed by the Herbal of Pseudo-Apuleius. During the Middle Ages these were revised and altered successively on a number of occasions by amanuenses. Nonetheless, they remain documents of fundamental importance to the history of medicine.
There are two types of herbals: one contains realistic illustrations in which the plant is shown as it appears in the wild; the other is schematic, in which the representation is embellished with symbols that indicate the plant's use.
In the herbals of the first type the plants are described in detail, with great attention paid to the quality of the illustration (whether in colour or black-and-white) and its curative properties. It is significant, for example, that an index of sicknesses appeared next to the index of the plants. The most important printed illustrated herbals during the Renaissance were those produced by Leonhart Fuchs (1542) and Pietro Andrea Mattioli (1565).
The second type of herbal was generally for personal use, and thus much closer to the tradition of popular medicine. The illustrations appeared more fanciful through their association with symbols and rituals. A classic example is mandrake, which is shown tied to a dog and the gatherer with his or her ears blocked so as not to hear the plant's shriek when it is pulled out of the ground.
A hortus siccus is a collection of dried plants either laid on or attached to sheets of paper. It has two functions: one, to record the presence of certain species of plant in a given area, and two, to allow comparison with samples from other areas.
A hortus vivusis like a botanical garden or collections of species contained in one. The purpose of the earliest botanical gardens, which were created originally in religious houses, was the cultivation of medicinal plants (called simple medicines, from which the term Garden of Simples is derived). Later, non-medicinal plants were also cultivated in these gardens for purposes of learning and science, in particular when botany split off from medicine as a separate science. From that moment botanical gardens became centres of experimentation and acclimatisation of species from the New World, for example, the potato and chilli.
From popular medicine to academic medicine: the sources
The Tacuinum Sanitatis is another medieval manuscript on the use of officinal plants.
The word tacuinum comes from the Arabic word taqwim, which means information or table. This type of text is the outcome of the Latin translation of an Arab work and was expressed in summary form (hence the reference to a table). It contains concepts of traditional medicine interpreted through behavioural practices and natural rhythms, at times linked with the study of astral influences. Plants are almost always shown whole in their natural environment and are accompanied by information on the best season to gather them and a description of how their properties alter with the change of the seasons.
In addition to offering remedies, the Tacuinum gives advice for staying healthy with regard to diet, hygiene and behaviour. By this last term it means having the right balance between wakefulness and sleep, movement and rest, joy and anger.
Manuscripts like these provide information on how to benefit from plants and how to avoid the harm they can cause. In short they are practical manuals for everyone, above all those who are interested in the conclusions offered by science rather than the proof, and are often adorned by colourful plant illustrations.
Prescription books contain more or less the same information as the herbals but organise it in a different manner. They aim to highlight the purpose for which a plant or herbal preparation is used. For each prescription or recipe, a list of ingredients is given with the method of preparation, the dosage and the means of administering it.
Unlike herbals, tables or prescription books, another printed form of plant-based information was the medical handbook, which came into use in the nineteenth century.
It differs from the previous information sources as it contains philosophical discussions on the reasons why and methods how certain plants should be used and gives a series of examples. The presentation of the information they contain differs because these handbooks were written for doctors, whereas the others discussed were for the use of apothecaries, chemists and herbalists.