Res′in.
A vegetable product composed of hydrogen, carbon, and oxygen.
Distinguishable generally from gum by its solubility in alcohol and insolubility in water, while gums are soluble in water and insoluble in alcohol.
There are many varieties of resins, derived from different species of trees.
Some are naturally combined with the gums, forming what are known as gum-resins.
Both these and the pure
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resins are generally termed gums.
Resins become negatively electrified by friction.
They are largely employed in making varnishes, and some are used as medicines.
The most common variety, known as
rosin, is derived from the distillation of crude turpentine.
Dr. Sacc of Nuenburg, Switz., gives the following summary as to the resins of commerce:—
Copal, amber, dammar, common rosin, shellac, elemi, sandarach, mastic, and Caramba wax can be reduced to powder.
The following will become pasty before melting; amber, shellac, elemi, sandarach, and mastic; the others will become liquid at once.
In boiling water, Caramba wax will melt; common rosin will form a semifluid mass; dammar, shellac, elemi, and mastic will become sticky; while copal, amber, and sandarach will remain unchanged.
Dammar and amber do not dissolve in alcohol; copal becomes pasty; elemi and Caramba wax dissolve with difficulty; while rosin, shellac, sandarach, and mastic dissolve easily.
Acetic acid makes common rosin swell; on all the others it has no effect.
Caustic soda dissolves shellac readily, rosin partly; but has no influence on the others.
Amber and shellac do not dissolve in sulphide of carbon; copal becomes soft and expands; elemi, sandarach, mastic, and Caramba wax dissolve slowly; while rosin and dammar dissolve easily.
Oil of turpentine dissolves neither amber nor shellac, but swells copal; dissolves dammar, rosin, elemi, sandarach, and Caramba wax easily, and mastic very easily.
Boiling
linseed oil has no effect on amber and Caramba wax; copal, shellac, elemi, and sandarach dissolve in it slowly, while dammar, rosin, and mastic dissolve easily.
Benzine does not dissolve copal, amber, and shellac, but does elemi and sandarach to a limited extent, and Caramba wax more easily; while dammar, rosin, and mastic offer no difficulty.
Petroleum ether has no effect on copal, amber, and shellac; it is a poor solvent for rosin, elemi, sandarach, and Caramba wax, and a good one for dammar and mastic.
Concentrated sulphuric acid is indifferent to Caramba wax; it dissolves all resins, imparting to them a dark brown color, excepting dammar, which takes a brilliant red tint.
Nitric acid imparts to Caramba wax a straw color; to elemi, a dirty yellow; to mastic and sandarach, a light brown; it does not affect the others.
Ammonia is indifferent to amber, dammar, shellac, elemi, and Caramba wax; copal, sandarach and mastic become soft, and finally dissolve; while rosin will dissolve at once.
It is not difficult by means of these reactions to test the different resins for their purity.
gum-resins.
| Common Name. | Botanical Name. | Native Place. | Quality, Use, etc. |
| Amber | | Prussia, Poland, etc. | Found in the mines, rivers, and sea-coasts of Prussia.
Used in varnish and for mouth-pieces of pipes. |
| Ammoniacum | Dorema ammoniacum | Persia, etc | Used as a stimulant in medicine. |
| Anime or Animi | Hymenaea courbaril | Brazil | Used for varnish.
The Indian kind known in commerce as “Indian copal.”
|
| Vateria indica | India |
| Asphalte | | Trinidad, Dead Sea, etc | Forms a basis of black varnishes, as Japan black, etc. Used with sand for paying material.
Affords petroleum or rock oil. |
| Assafoetida | Narthex assafoetida, etc. | Central Asia | Used as a stimulant and antispasmodic in medicine. |
| Australian gum-resins | Eucalyptus (various) | Australia | Affords resins for varnishes, and produces tannin. |
| Tasmania |
| Balata | Achras dissecta | Guiana | One of the Sapoteae; allied in qualities to gutta-percha. |
| Benzoin or Benjamin | Styrax benzoin | E. Indian Islands | Fragrant.
Used incense, perfumery, pastilles; affords benzoic acid. |
| Canada balsam | Abies balsamea, etc | Canada | Becomes solid on exposure to the air. Used to mount microscopic objects, for varnish, and as a cement for optical glasses. |
| Caoutchouc | Siphonia brasiliensi | Brazil | The solidified milky juice of many families of plants.
Is very elastic; has the property of uniting with sulphur, magnesia, etc.; is used for submarine coating, etc.; is of the highest value in mechanics and manufactures. |
| Ficus elastica, etc | East Indies |
| Urceola elastica | E. Indian Islands |
| Copal | Hymenaea (various) | W. Africa, E. Indies, South America | Used for varnish. |
| Dammar | Dammara australis | New Zealand. | Used in making varnish.
Obtained from Cowdi pine.
Found where the tree has formerly grown. |
| Dragon's blood | Calamus draco | East Indies | Deep reddish-brown color.
Used (after being dissolved in alcohol) for staining material for marble, wood, leather, etc., and to color varnishes. |
| Canaries |
| Dracaena draco, etc | South America |
| Elemi | | Tropics | Ointment, plasters, varnish. |
| Galbanum | Ferula galbaniflua | Levant | Used in pharmacy. |
| Gamboge | Cambogia gutta | Cambogia, Siam, etc | Yellow.
Used as a pigment and as a gold lacquer, etc. |
| Hebradendron |
| Gambogioides, etc |
| Geranium | Monsonia burmanni | S. Africa | Produces much resin.
Found in the sands about the Cape of Good Hope.
The resin is produced after the death of the plant. |
| Gum-dragon | (See Dragon's blood.) |
| Gutta-percha | Isonandra gutta | Malay Islands | The solidified milky juice of many species of Sapotaceae.
Being plastic when heated, is used in molding, electroplating, etc. Is a bad conductor of both heat and electricity. |
| Indian copal | Vateria indica | India | Called “Piney varnish.”
Similar to animi. |
| India-rubber | (See Caoutchoue.) |
| Kind | Pterocarpus erinaceus. | Gambia | Used as an astringent in medicine. |
| Lac | Ficus religiosa | India | Resin produced by the puncture of a hemipterous insect on the tree, especially the “Peepul.”
Sold in commerce as shellac, threadlac, blocklac.
Used to make sealing-wax, glass-cement, varnishes, and for bodies of hats, etc. |
| Butea frondosa |
| Mastic | Pistacia lentiscus | Scio | Used for varnish.
Employed by dentists.
Aromatic, astringent. |
| Myrrh | Balsamodendron myrrh | Shores of Red Sea | Used as an antispasmodic, stomachic, etc., and in toothpowder. |
| Piney varnish | (See Animi and Indian copal.) |
| Pitch | Pinus sylvestris | Sweden, etc | The residuum of the distillation of pyroligneous acid from wood-tar. |
| Rosin | Pinus palustris, etc | North America, etc | The residue left after the distillation of oil of turpentine |
| Sandarach | Callitris quadrivalvis | Algiers | Used in varnishes.
When powdered, affords pounce.
Incense. |
| Scammony | Convolvus scammonia | Asia Minor | Used as a purgative in medicine. |
| Shellac | (See Lac.) |
| Storax | Styrax officinale | Asia Minor | Soft; unctuous, and used as an expectorant. |
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| Common Name. | Botanical Name. | Native Place. | Quality, Use, etc. |
| Storax (liquid) | Liquidumber | United States | Fragrant; bitter; expectorant. |
| Tar (wood) | Pinus sylvestris | North Carolina, Sweden, and Russia | Obtained by slow distillation of the branches and roots of the pine, etc., whilst burning in a nearly closed pit. |
| Turpentine | Pinus palustris | America | Used in medicine, painting, and as a solvent for reins. |
| Turpentine (Strasburg） | Abies picea | Europe |
| Turpentine (Venice） | Larix europoea | Europe |
gums proper.
| Gum-arabic | Acaia arabica et vera | N. Africa, Asia, etc. | Finest of the gums.
Soluble in water. |
| Gum (British) | Solanum tuberosum | Britain, etc. | Torrefied potato-starch.
Called dextrine. |
| Gum-tragacanth | Astragalus tragacantha, etc | Asia Minor, Persia | For mucilage and as a substitute for gum-arabic. |
| Gum (various) | Pyrus, prunus, etc. | Britain, etc | Soluble in water.
Exudes from apple, pear, cherry, and other trees. |
