620 METHODS AND FORMULAS AMS 21.1-AMS 22,1 



21.1 Uyama 1926 8542a, 4:389 



formula: water 100, 40% formaldehyde 12.5, pyrogallol 1.75 



21.1 Warthin -Starry 1929 test. 1942 Langeron Langeron 1942, 630 



STOCK solutions: I. 10% gelatin; II. 10% starch; III. 2.5% hydroquinone in 40% 



acetone; IV. 2% silver nitrate 

 preparation: Prepare 50 ml. each I and II, dissolving the first with warm and the 



second with boiling. Mix. Take 6 ml. Ill and add to mixture. 

 working solution: immediately before use mix 5 parts of the above mixture with 1 



part stock IV 



21.1 Weber 1944 4285a, 21 :45 



formula: water 100, 40% formaldehyde 5, hydroquinone 2, sodium citrate 1 



21.1 Wilder 1936 608b, 11:817 



formula: water 100, 40% neutralized formaldehyde 0.5, uranium nitrate 0.015 



21.1 Willard 1935 17510,87:475 



formula: water 90, 40% neutralized formaldehyde 10, hydroquinone 1 



21.1 Yamanoto 1909 23681,20:153 



formula: water 100, pyrogallol 2, tannic acid 1 



22 Toning or Metal Exchange Solutions 



Toning depends for its value on tlie fact that a solution of gold will replace metallic silver, 

 or many silver compounds, in the solid state. The principle use is either to render more ap- 

 parent weakly stained materials, or to improve the keeping qualities of the preparations on 

 the ground that gold is less subject to natural deterioration than is silver. The simple solu- 

 tions of gold chloride usually employed are listed with the staining techniques in Chapter 22. 



22.1 formulas 



22.1 Balbuena 1922 21344,20:31 



formula: water 100, sodium borate 1, gold chloride 0.1 



22.1 Bodian 1936 763, 65:89 



formula: water 100, gold chloride 1, acetic acid 0.1 



22.1 Cajal 1910 21344, 8:1 



formula: water 100, ammonium thiocyanate 3, sodium thiosulfate 3, 1% gold chloride 

 0.2 



22.1 Cajal 1921 21344, 19:71 



formula: water 100, ferric alum 4, oxalic acid 1 



22.1 Cajal test. 1948 Lillie Lillie 1948, 101 



formula: water 100, ammonium thiocyanate 3, sodium thiosulfate 3, gold chloride 0.01 



22.1 Cajal and de Castro 1933 see AMS 24.1 Cajal and de Castro 1933 



22.1 Foot 1927 1887a, 4:43 



formula: water 100, gold chloride 0.2, mercuric chloride 0.5 



22.1 Golgi 1908 tod. 1933 Cajal and de Castro Cajal and de Castro 1933, 202 



STOCK solutions: I. water 100, sodivim thiosulfate 3, ammonium thiocyanate 3; II. 1% 



gold chloride 

 WORKING solution: stock I. 100; stock II. 1.5 



22.1 Lancelin, Seguy, and Dubreuil 1926 6630, 94:557 



formula: 1% sodium thiosulfate 30, 1% ammonium thiocyanate 30, 1% gold chloride 

 30 



22.1 Sand 1910 6593,12:128 



formula: water 85, 2% solution ammonium thiocyanate 15, 2% gold chloride 3 



