Natural History . 413 



been found in the United States, that the decoction of the bark of a 

 sumach (Rhus glabrum) has, in this respect, remarkable powers. 

 Care must be taken not to confound this species with the Rhus 

 vernix, which very much resembles it, for the latter is acrid, and, 

 according to Dr. Fahnestock, produces injurious effects. In the 

 genus of sumach there are aromatic as well as poisonous species. Of 

 the former kind are the Rhus suaveolens, and Rhus aromaticum, both 

 of North America *. 



4. RELIEF FOR THE TOOTH-ACHE. 



The following account is by Dr. Ryan, who himself testifies to the 

 efficacy of the remedy recommended. * Like many of our best reme- 

 dies, that which I proceed to notice (for the tooth-ache) was disco- 

 vered by accident. A gentleman who attends my lectures (Mr. 

 Myers, of Newington Causeway) had frequently applied sulphuric 

 acid to his tooth with some relief, but on one occasion, he, in a 

 moment of confusion, took down the next bottle to his remedy, which 

 contained nitric acid : to his great surprise he experienced immediate 

 relief and without the slightest pain. Since that period he has not 

 suffered from tooth-ache, though three years have now elapsed. 

 During the last winter he informed me of the success of this remedy, 

 which induced me to try it while labouring under the most intense 

 pain from tooth-ache. The effect was immediate, and no pain whatever 

 was induced. I have since used it in numerous cases, and invariably 

 with complete success. In some instances the disease does not 

 return for days, or weeks, and in others not for months/ 



The best mode of employing it is by means of lint wrapped round 

 a probe and moistened with the acid, which is then to be slowly 

 applied to the cavity of the tooth, care being taken not to touch the 

 other teeth, the gums, or the cheeks. On withdrawing the probe and 

 inquiring how the patient feels, the usual reply is, ' The pain is entirely 

 gone.' The mouth is next to be washed with tepid water. The acid 

 should be gradually applied to the whole cavity of the tooth, or other- 

 wise a second application will be required before complete relief will 

 be obtained. 



This remedy may be used when the gum and cheek are inflamed so 

 as to preclude the possibility of extraction. In \cases where the 

 diseased fang remains, and when the caries faces the adjacent tooth, 

 it obviates the necessity of extraction in all cases of hollow teeth, 

 which all practitioners declare to be desirable if possible, and it 

 enables the dentist to perform the operation of * stopping or filling 

 teeth ' much sooner than he can otherwise accomplish. In a word, 

 it will alleviate a vast deal of human suffering and supersede a most 

 painful operation. It does not accelerate the decay of the tooth to 

 wliich it is appliedf. 



* Jour, de Pharm., 1831, p. 391. f Lou. Med. Jour., vii. p. 56. 



