ORDER ANNULATA APODA. Ill 



sufficiently large, keeping- the water clear, and in re- 

 moving those which are unhealthy as soon as they are 

 discovered. 



Leeches, when applied to the skin, frequently show 

 little inclination to bite, and many plans have been 

 resorted to, to induce them to commence operations, 

 such as bathing] the part with milk, &c. ; but these 

 methods may be considered useless, and the best plan 

 appears to be, to wash the part clean, and this is the 

 more necessary when any embrocation has been pre- 

 viously applied ; but the surest way is to puncture the 

 place slightly, so as to cause the blood to appear. If the 

 little surgeon, before it is fully gorged, appears lazy and 

 unwilling to proceed, it can be usually roused by being 

 sprinkled with a little cold water. 



After a leech has fallen off, it is usual to sprinkle 

 salt on it to induce it to disgorge the blood it has swal- 

 lowed ; but as the salt frequently blisters its body, it has 

 been recommended by Dr. Johnson of Edinburgh, from 

 whose work on the Leech, we have obtained most of the 

 preceding information, to apply a small portion of vinegar 

 to the head of the leech instead of salt. 



The necessity for obliging the leech to dislodge the 

 blood it has swallowed, arises from the fact that it would 

 remain in the body of the animal for some months before 

 it could be all digested ; but the most singular thing is, 

 that, during the whole of this time, the blood remains in 

 nearly as tluid a state as when it was newly swallowed*. 



* It has been quaintly said on the subject of depriving the leech of its 

 food, that " Those persons do not consider that blood is the most favourite 

 and salutary nourishment of this extraordinary creature ; and I would 

 ask such inconsiderate persons how they would feel themselves, if, im- 

 mediately after eating a hearty dinner, any person was to give them a 

 violent emetic." 



