The constitution of Argentum nit. is that of the prematurely old. It is especially applicable to those deep, boring pains in the bones simulating syphilitic bone pains, both in character and in the time of aggravations, when associated with the symptomatology of the remedy. It is not unlike Argentum met. in its symptomatology, but differs in that Argentum met. attacks cartilaginous tissue while Argentum nit. attacks bony structures. NECK AND BACK. — (Argentum nitricum) (Acute pain in dorsal region.) Cutting pain in small of back and groin. Pain in small of back > when standing or walking ; but severe when rising from a seat. Sense of weight in lower part of sacrum and coccyx > while standing, < while sitting. SMALL OF BACK FEELS WEARY ; HEAVINESS AND DRAWING IN LOINS, WITH DEBILITY AND TREMBLING OF LEGS. PAIN IN SMALL OF BACK, < EVENINGS. SUPERIOR EXTREMITIES . — (Argentum nitricum) Drawing pain in shoulder ; in left shoulder and arm. (Left arm feels heavy.) BORING PAIN IN BONES OF ARM, ESPECIALLY IN EVENING. HANDS TREMBLE. Rheumatic pain in right arm. INFERIOR EXTREMITIES . — (Argentum nitricum) Debility and weariness of lower limbs, as after walking a long distance, accompanied by a sick feeling ; dread of work, drowsiness, chilliness and sick appearance. Paralytic heaviness and weakness of limbs. BORING IN KNEES STARTS UP IN EVENING. Calves weary as after a long walk. EXTREMITIES IN GENERAL . — (Argentum nitricum) TREMBLING OF LIMBS. WEARINESS AND WEAKNESS OF LIMBS. Paralysis of limbs. AFFECTIONS OF BONES. CONCOMITANTS . — (Argentum nitricum) SAD AND DESPONDENT. LOSS OF MEMORY.