For the mode of obtaining this substance from opium, the reader is referred to the U. S. Dispensatory. It exists uncombined in opium, which while agreeing in this respect, were severally distinguished by peculiar properties of their own.

Morphia induced profound sleep, with sensibility blunted but not quite lost; as severe pinching caused obvious uneasiness, and sudden sounds occasioned movements of the animal, showing that they were heard. But there was a striking peculiarity in the mode of awaking. The animals exhibited an aspect as if startled or alarmed, and their hinder limbs were depressed as if partially paralyzed, so as to give to a dog the carriage of the hyena. The dog, too, under these circumstances, did not recognize his master, and sought to retire into some place where he could be hidden. Twelve hours elapsed before these effects had entirely disappeared.

Codeia, in whatever dose exhibited, produced a less profound sleep. The animal could be easily aroused, and sensibility was much less blunted. On awaking from the sleep produced by it, the animal exhibited less disorder of his faculties, and had none of the semi-paralyzed condition of the hinder limbs, mentioned as resulting from morphia.

Narceia caused a sleep differing from that of either of the other alkaloids, yet partaking of the nature of both. It was in the same dose more soporific than either: the sleep produced being more profound than that of codeia, without the leaden torpor caused by morphia; and the sensibility, though blunted, being much less so than by the latter alkaloid. The action of the narceia was characterized by calmness and want of excitability. The animal was not disturbed by any sudden noise, and on awaking, quickly returned to its normal state, with much less of the posterior weakness and mental confusion that marked the action of morphia. Narceia is peculiarly suited to the experimental physiologist; as the animal is perfectly passive under his hands, and makes no resistance even though in pain. The same effects produced by narceia on the lower animals were found by Drs. Debout and Behier to be caused by it in man.

In reference to the poisonous action of the several principles ; morphia is one of the least poisonous, thebaina the most so. Thus, a grain and a half of the muriate of thebaina, injected into the veins of a dog, killed the animal in five minutes; while thirty grains of the muriate of morphia, similarly exhibited, did not cause death. Next in poisoning power to thebaina was codeia. Much less of this then of morphia, injected into the veins, was required to cause death.

Another point of comparison between the alkaloids was in regard to their convulsive effect. While they poison, they also occasion convulsions of a tetanic character, sometimes violent. The only exception is narceia, which occasions no convulsions even in a fatal dose; the animal dying in a complete state of relaxation.

On the whole, then, the conclusions were that three of the alkaloids are soporific: namely, in the order of their power, 1. narceia, 2. morphia, and 3. codeia; the three others, not soporific, are convulsive, and all six in the order of their power in this respect are 1. thebaina, 2. papaverina, 3. narcotina, 4. codeia, 5. morphia, and 6. narceia. In their tonic powers, they have the following order; 1. thebaina, 2. codeia, 3. papaverina, 4. narceia, 5. morphia, and 6. narcotina. (Archives Generates, 6e ser., iv. 455).

Therapeutic effects of the opiate alkaloids. This subject has been practically investigated by Dr. Ozannne, who has published the following results of his observations. Pseudo-morphia and mecsnin are destitute of action.

Morphia acts on the whole nervous system, first on the bruin, then on the spinal cord, and lastly on the ganglionic system, as evinced by the expansion of the capillaries.

Opiania is little known in regard to its effects, but is thought to be calmative and stupefactive like morphia.

Codeia is excitant, calmative, or stupefactive, according to the dose. Three or four grains stupefy like morphia, or prove anaesthetic like ether or chloroform. In very small doses, it calms, without exciting or but slightly. In moderate doses, it first excites and then calms. Its special influence appears to be exerted on the cerebellum and medulla oblongata. A disposition to retrogression in the movements has been observed daring its action, and, after death from it. the parts mentioned are found engorged with blood. Hence its usefulness in coughs and gastralgic affections, acting through the pneumogastric nerve.

Narcotina is always excitant in its influence on a debilitated system, and. even in the dying state, it will for a time revivify the vital actions. The dose of it required for this effect is from five to ten centigrammes (about three-quarters of a grain to a grain and a half). It excites the pulse and increases the warmth of the body, without in the least stupefying.

Thebaina is more violent in its action than narcotic. In moderate doses, it agitates and even tetanizes, and occasions sleeplessness rather than the contrary. Its influence in producing tetanic spasm is exerted especially on the upper limbs, suggesting that it may perhaps prove useful in palsy of the parts. The author gave from three to six centigrammes (about half a grain to a grain) to a patient with paraplegia, but found the medicine to produce so much general uneasiness, and excitation, especially of the upper extremities, together with sleeplessness, that he was compelled to suspend it.

Narceia is a valuable calmative. In the dose of one or two grains, though it may not produce sleep, it gives the patient a feeling of calmness and perfect comfort; and produces these effects sometimes when morphia will not. It appears to exercise a special influence on the lumbar portion of the spinal cord. (Ed. Med. Journ., Nov. 1864, p. 459; from Revue de Therap. Medico-chirurg., Oct. 15, 1864).

Of the same alkaloid we are told that, of all the alkaloids of opium, it produces physiological sleep in the smallest dose. In a child, 10 years old, with phthisis, given in the quantity of about one-seventh of a grain through the day, it produced sleep and relieved the cough beyond all other means employed. (Ibid., April, 1865, p. 947; from Gaz. Med. de Paris, March 11, 1865.) - Note to the third edition.

Very different opinions have been advanced as to its effects on the system. While some have found it very powerful, and have ascribed to it noxious properties, others have taken or given it largely, without any observable effect, whether it was taken in the solid state or in solution. Twenty, thirty, and, as asserted by M. Baily, even sixty grains have been given with entire impunity. The probability, therefore, is that, when pure, it has little narcotic influence upon the system, and that the effects at first ascribed to it have resulted from the use of an impure preparation, containing morphia, or some other active principle of opium. Dr. Roots, of England, was induced by the bitterness of its salts to employ it in intermittent fever; and Dr. O'shaughnessy, of Calcutta, gave it with the happiest results in a great number of cases, considering it superior even to quinia in antiperiodic powers. He gave it in the dose of three grains three times a day, and never found it to produce narcotic effects, headache, nausea, or constipation, but to act powerfully as a diaphoretic. It is contained in opium in very varying proportions, from two to nine or ten per cent., and is generally most abundant when morphia is least so.

Denarcotized Opium

Denarcotized Extract of Opium. - Denarcotized Laudanum. Under the impression that opium owed its unpleasant effects to narcotina, preparations were introduced into notice and extensive use, in which the medicine was deprived of this principle, retaining its other principles unchanged. Thus, opium or its extract was deprived of narcotina by ether, and a tincture was prepared from the denarcotized extract by treating it with diluted alcohol, so as to have about the strength of the ordinary tincture, and this has been called denarcotized laudanum. But, as before mentioned, it is extremely doubtful whether pure narcotina exercises any obvious influence on the system; and, if the preparations referred to have any advantage over the ordinary extract and tincture, the fact must be ascribed to some other modification of opium than the mere absence of this principle. The officinal deodorized tincture of opium (see page 757) renders unnecessary all other preparations in which the object is to get rid of narcotina.