36 INSECT MISCELLANIES. 



swelled to double their natural size, and black, except 

 a few, which appeared torpid and feeble, and soon 

 died on exposure to the air*. 



It may be, that the honey collected from deleterious 

 plants is only noxious in considerable quantity, which 

 we may illustrate by the instance of the oxalic acid. 

 In small proportions this is not uncommonly used to 

 acidulate punch, and to make an acidulous beverage 

 similar to lemonade, of which we ourselves have 

 frequently drunk without the slightest bad conse- 

 quences; but when taken in the quantity of an ounce 

 or more, as it usually is when mistaken for Epsom 

 salts, it but too often produces death t- Captain 

 Beaufort furnishes a still more striking illustration 

 in his excellent account of Karamania. In an excur- 

 sion to the country, his people, fatigued with heat 

 and thirst, were about to drink of a river of pure- 

 looking water, but were told by the guides that it 

 was certain poison, though, upon a cautious trial, 

 they found it well tasted. The ingenious rules, 

 therefore, which Dr. Abercrombie, of Edinburgh, 

 has devised for judging of the qualities of food and 

 medicine, by taste alone, would in these cases be 

 quite at fault. 



It is a remark which will be found to hold good, 

 both in animals and vegetables, that no important 

 motion or feeling can take place without the pre- 

 sence of moisture. In man, the part of the eye which 

 is the seat of vision is always bedewed with moisture ; 

 the skin is softened with a delicate oil ; the sensitive 

 part of the ear is filled with a liquid ; but moisture 

 is still more abundant in our organs of taste and 

 smell than in any of the other senses. In the case 

 of taste, moisture is supplied to our mouth and tongue 



* Nicholson's Journal, xxiii. 234. 



•f- See Rennie's New Supplement to the Pharmacopseias,-^ 

 Jtrt, Oxalic Acip, 



