II.—THE "RED-BARK" REGION, ON THE WESTERN SLOPES OF CHIMBORAZO.
The species yielding "red bark," the richest and most important of all the Chinchonæ, is found in the forests on the western slopes of Mount Chimborazo, along the banks of the rivers Chanchan, Chasuan, San Antonio, and their tributaries. So early as 1738 Condamine spoke of "red bark" (cascarilla colorada) as being of superior quality;[48] and Pavon sent home specimens of the "red bark of Huaranda," and named the species C. succirubra. Some of these are now in the British Museum; and in the collection of Ruiz and Pavon, in the botanical gardens at Madrid, I found capsules, flowers, and leaves marked "cascarilla colorada de los cerros de San Antonio." In 1857 Dr. Klotzsch, an eminent German botanist, read a paper at Berlin,[49] elaborately describing the "red bark" as a product of C. succirubra, from a very good specimen of Pavon's in the Berlin Museum. Mr. Howard has also received a specimen from Alausi, and he is inclined to the belief that there are several varieties of C. succirubra, and one or two allied species, as yet undescribed.[50] Much light was thrown upon the history of this valuable species by Mr. Spruce, when he penetrated into the forests to collect seeds and plants for transmission to India in 1860.
Though little was known of the tree until quite lately, there was never any doubt concerning the value of the bark. In 1779 a Spanish ship from Lima, bound to Cadiz, was captured off Lisbon by the 'Hussar' frigate, and her cargo consisted chiefly of "red bark," part of which was imported into England. In 1785 and 1786 Ruiz states that the collectors began to gather the bark of C. succirubra, and sell it at Guayaquil, and from that time it continued to be found in the European markets. It contains a larger proportion of alkaloids than any other kind, amounting to as much as from 3 to 4 per cent. of the substance of the bark, and of this a fair share is quinine. Fine samples yield 3.9 per cent., selling at 8s. 9d. per lb.; and the quill bark from the smaller branches 3.6 per cent.[51] Mr. Howard has recently procured 8.5 per cent. of alkaloids from a specimen of "red bark." A large supply of plants of this species is flourishing in India and Ceylon, and, from the richness of the species, the comparatively low elevation at which it thrives, and its hardy nature, it may be expected to become a cultivated plant of great value and importance.
In 1857 the export of bark from the port of Guayaquil, the place of shipment for the C. succirubra, amounted to 7006 quintals, valued at 23,353l.[52] In 1849-50 Dr. Weddell gives the amount at 1042 quintals.
III.—THE NEW-GRANADA REGION.
The importance of the chinchona-trees was fully established in the middle of the last century, and, Don Miguel de Santistevan, the director of the mint at Bogota, having addressed a memorial on the bark trade (estanco de cascarilla) to the Viceroy Marquis of Villar in 1753, the attention of the Spanish Government was seriously turned to the subject. When the Viceroy Don Pedro Mesia de la Cerda, Marquis de la Vega de Armijo, went out to Bogota in 1760,[53] he was accompanied by the botanist Don José Celestino Mutis, a native of Cadiz, who was appointed to conduct a botanical survey of New Granada, and especially to investigate the bark of the chinchona-trees.[54]
In 1772 Mutis found these trees in the neighbourhood of Bogota, and described four kinds in 1792, which he called C. lancifolia, C. cordifolia, C. oblongifolia, and C. ovalifolia, yielding four kinds of barks—anaranjada, amarilla, roja, and blanca, or orange-coloured, yellow, red, and white.[55] He declared the C. lancifolia to be excellent for intermittent fevers, in which he was right, and to be identical with the C. Condaminea of Loxa, in which he was wrong; the C. cordifolia he recommended for remittent fevers, and the other two for inflammatory diseases. In reality the two last are not chinchonas at all, but belong to the genus Ladenbergia, and contain no fever-dispelling alkaloids whatever; while the C. Cordifolia is so poor in alkaloids as to be practically worthless.
While Mutis, and his disciples Caldas and Zea, were prosecuting their researches in New Granada, an expedition under the botanists Ruiz and Pavon was sent to Peru; and an acrimonious paper war sprang up between the rivals, as to the respective merits of the barks of New Granada and Peru. Ruiz declared the New Granada kinds to be inferior to those of Peru, while Mutis contradicted him, and Zea[56] went so far as to maintain that the species found by Ruiz and Pavon in Peru were mere varieties of the four chinchonas of Mutis, growing near Bogota.[57]