The symptoms are bloody passages, great pain and distress, and vomiting of blood. There is no cure for this, and it is merciful to destroy the poor animal at once, ending his suffering by chloroforming.

I now conclude this article by giving one that was published in the American Stock-Keeper:

"Phosphorous is a dangerous poison, and will be got from rat-paste which is left lying about, spread on bread and butter. For this give an emetic, followed by a draught of Magnesia and water. Afterwards milk and other demulcents, with a few drops of laudanum to allay pain. Mercury may be taken in several forms - either as Calomel, 'White Precipitate,' or 'Corrosive Sublimate' - all of which are accessible to dogs at various times. Give large draughts of white of egg beaten up with water; an emetic first. Then diet on milk and broth. If violent purging, give a little laudanum. Sulphate of copper is in common use about farms, and so is dangerous to dogs, who may pick up and devour dead birds in a corn field in which the seed has been dressed with this poison. Its antidotes are demulcents (after the usual emetic), such as white of egg and milk, and a little laudanum later. It will be seen from the forecoming that the treatment for all mineral poisons is very similar all round.

"Now, as to vegetable poisons, or, to be more precise, organic poisons (minerals being inorganic). The chief of these, as far as they affect dogs and their owners, are Aconite, Belladonna, Digitalis ('Fox-glove'), Opium Strychnine and their various compounds or derivatives. First, then, Aconite, which is often given as a medicine, and of which it is easy to give an overdose. Give an emetic, and then proceed with stimulants - • brandy, etc. Keep warm, and try artificial respiration if need be. For Belladonna similar treatment. Good hot drinks of stimulants. Foxglove (Digitalis) - often prescribed for heart affections in dogs, as well as in men for this, after an emetic, give warm tea, followed by stimulants. Opium, the active principle of which is morphia, needs a good emetic, followed by a draught of brandy and water; every effort must be made to subdue drowsiness by brisk exercise until the effect has worn off. Lastly, Strychnine -deadliest of poisons - a component of all vermin killers - easily recognized by its effect on the muscles. Give an emetic, followed by doses of Potassium Bromide every twenty minutes, and later a dose of Castor Oil. Strychnine is, as we have stated earlier, the most active principle of Nux Vomica."

Here is also, some good advice on strychnine poisoning that I found some place, and worth including:

"Strychnine poisoning, unfortunately, is so rapidly fatal that the dog is usually found dead or dying. If there has been immediate vomiting or only a small dose swallowed, the chances of recovery are good when the proper means are available. If vomiting has not occurred, produce it by giving a warm solution of common salt (a tablespoonful to the pint) in large doses until the stomach is well emptied. After this the most important object is to produce stupor, and morphine, hypodermically administered, as well as being a good emetic, is a safe narcotic in the dog. In dogs over six months old one-fourth grain can be given safely for every ten pounds of live weight. This should be followed by chloroform inhalation administered lightly and kept up until the convulsions become less pronounced. Chloral hydrate is probably the best antidote in cases where it cannot be given by the mouth owing to spasm of the cheek muscles. It should be given in from ten to thirty grain doses, dissolved in an ounce of warm water, injected gently in the rectum. The dose can be repeated if considered necessary every hour. The animal suould be kept as quiet as possible, harsh sounds, bright lights or unnecessary handling tending to increase the severity of the convulsions."