PLANTS PRODUCING GUMS AND RESINS 317 



never in any case shows the fresh and really fine ori.ninal colour of 

 the gum. 



Two other species have been observed to give a similar gum to 

 that of Butca froniosa; they are : />'. SH-perhcij in which the pedicles 

 of the orange-yellow flower are larger than those of B. jronciosa; and 

 B. -parviflora, distinguished from the two others by its small whitish 

 flowers. 



Cordyla africana. — An African plant which yields gum. 



Dalbergia laccifera. This tree is used to rear the Coccus lacca, 

 and in Cambodia yields from 10 to 20 kilos of lac per annum. 



Ferreirea spectabilis. — A Brazilian tree, the wood of which harbours 

 enormous quantities of a very volatile resin. 



Flemingia Crahamiana. — This leguminous plant produces a red 

 resin called ftcinnii:,in. 



Myroxylon Pereirae. — Like the species Myroxylon -pubesct-ns, this is 

 a tropical American tree, growing in the State of San Salvador. It 

 yields the product known as Peru balsam. This is a soft, liquid pro- 

 duct of dark brown colour, with an agreeable smell and a bitter 

 flavour. It contains cinnamic acid and several resins. 



Peru balsam is used in medicine as a slightly bitter stimulant ; it 

 is recommended for bronchitis and laryngitis. Il is imported into 

 Europe in large quantities, chiefly for perfumery. Its odour recalls 

 that of vanilla; when added to soap it imparts its scent and causes 

 the soap to lather. Peru balsam is used in the Catholic ritual for 

 the preparation of holy oil. 



M. Dorat, Technologist to the State of San Salvador, has made 

 an exhaustive study of the balsam-producing tree, and we ciuote the 

 following passages from his work : — 



" The tree begins to produce when five years old and lives for a 

 very long while. The collecting of the balsam begins with the dry 

 period, in the early days of September. The bark, up to a certain 

 height on all four sides, is beaten with the back of a hatchet until it 

 becomes detached from the woody portion, but it is not torn or 

 damaged. During this operation four intervening bands of bark are 

 left, so as not to destroy the vitality of the tree. 



" Several slits or incisions are then made in the beaten bark by 

 means of a sharp instrument, and a light is applied to the openings. 

 The balsam which flows out catches fire; it is allowed to burn for a 

 time and the fire is then put out. 



" The tree is left in this state for a fortnight and kept under close 

 observation; at the end of this time the balsam begins to flow pro- 

 fusely and is caught on cotton rags stuffed in the slits. When these 

 rags are saturated they are pressed and placed in earthen pots with 

 boiling water, and the balsam soon floats at the surface after the 

 manner of oil. Balsam is only extracted from the tree during four 

 days of the week, and the average yield is i to 2 kilos per week. 



" As soon as exudation begins to slow down, new incisions are made 

 in the bark, a light is applied once more, and, in a fortnight's time. 



