THE MICROSCOPE IN PHYSIOLOGY. 99 



cine "), " to the subject of adulteration, has furnished 

 the means of detecting a host of adulterations, the 

 discovery of which had before, for the most part, 

 been considered to be impossible." By means of the 

 microscope, the various forms of cellular and other 

 tissue, starch granules, woody fibres, spiral vessels, &c. 

 &c.,are revealed; as the various substances have their 

 distinctive characteristic forms, a mixture of one or 

 more substances with what is sold as a pure and 

 unadulterated substance, becomes evident. The fol 

 lowing remarks of Dr. Hassall, one of our highest 

 authorities on food adulteration, will be read with 

 interest : 



"When we survey with our unaided vision any 

 animal or plant, we detect a variety of evidences of 

 organisation or structure ; but there is in every part 

 of every animal or vegetable production an extra- 

 ordinary amount of organisation wholly invisible to 

 the unarmed sight, and which is revealed only to the 

 powers of the microscope. Now this minute and 

 microscopical organisation is different in different parts 

 of the same animal or plant, and different in different 

 animals and plants, so that by means of these 

 differences, rightly understood, the experienced micro- 

 scopical observer is enabled to identify in many cases 

 infinitely minute portions of animal or vegetable tissues, 

 and to refer them to the parts or species to which they 

 belong. 



" Thus by means ot the microscope, one kind of 

 root, stem, or leaf may generally be distinguished from 

 another ; one kind of starch or flour from another ; one 

 seed from another, and so on. In this way, the micro- 

 scope becomes an invaluable and indispensable aid 

 in the discovery of adulteration. 



" Applying the microscope to food, it appears that 

 there is scarcely a vegetable article of consumption, 



G 2 



