178 

 whether in the diluted state, or in combination with 

 substances of low affinity, is particularly destructive 

 in this respect. The patient who now takes the 

 soluble preparations of iron, is provided with an 

 instrument to convey the liquid into the pharynx, 

 and prevent any portion of it from coming in contact 

 with the teeth. Those who swallow such a form of 

 medicine, without employing the tube, soon exhibit 

 the consequence in the general discolourization and 

 decay of the mouth. The man, however, gulps his 

 physic, and can rince out his mouth if the taste be 

 retained; the horse, when it takes a drench, holds 

 the liquid for a considerable time before it swallows, 

 and the administration of the fluid is not very quickly 

 accomplished. Now, in proportion to the duration of 

 contact would be the effect ; and if the hasty deglu- 

 tition of the one being cannot save the teeth from the 

 ravage of the sulphate, is the prolonged retention 

 of the substance likely to be without effect upon the 

 same organs in the other ? The horse, however, 

 takes the sulphates of a strength which the human 

 being would not survive — where the one for a dose 

 swallows a grain, the other may imbibe a drachm. 

 The consequences must bear some proportion to the 



