Inorganic Substances 43 



8-hydroxyquinoline for the demonstration of manganese. In 

 an oxidizing medium it is supposed to stain manganese 

 brown-black. The method has not been tested on animal 

 material, but it appears unhkely that it will prove sensitive 

 and selective enough, especially in the presence of much 

 larger amounts of iron. 



Metals Occurring under Experimental or 

 Pathological Conditions 



thallium 

 Method of Barhaglia^^ 



Fix tissues in 95 per cent alcohol containing 2-5 per cent 

 of iodine and 5-10 per cent of potassium iodide. Thallous 

 iodide precipitates in the form of yellow crystals. This is an 

 untested method. 



BERYLLIUM 



Method of Denz'^'^ 



Fix in formalin or formalin-alcohol. Mix equal volumes of a 

 fresh 0.5 per cent solution of Naphthochrome green B and 

 of phosphate buffer pH 5.0. Stain sections in this mixture for 

 30 minutes at 37° C. Wash in water, differentiate in absolute 

 alcohol. Wash once more; counterstain with acridine red. 

 Dehydrate and mount. Be stains apple green. Iron and alu- 

 minum give somewhat different green shades. This is an un- 

 tested method. 



Lead— The two methods described for the demonstration 

 of this element are based on the insolubility of its yellow 

 chromate and its brown-black sulfide, respectively. 



The chromate method"^^ is for use with tissues not re- 

 quiring decalcification. The reagent (potassium dichromate) 



46. Barbaglia, V.: Studi Sassari, 8:253, 1930. 



47. Denz, F. A.: Quart. J. Micr. Sc, 90:317, 1949. 



48. Cretin, A.: Compt. rend. A. anat., 16:241, 1929; Frankenberger, Z.: 

 Compt. rend. A. anat., 16:241, 1921. 



