V 32.1 VARIOUS FORMULAS 665 



32.1 Harting (est. 1877a Frey Frey 1877, 111 



formula: water 60, gelatin 20, lead acetate 5, potassium dichromate 2.7 

 preparation: Dissolve lead acetate in 20 water. Dis.solve dichromate in 40 water. Mix 

 slowly and with constant agitation with acetate solution. Heat to 35°C. Soak gelatin 

 in water. Drain. Melt and incorporate with warm lead chromate mass. 



32.1 Harting test. 1877b Frey Frey 1877, 112 



formula: water 11.5, gelatin 25, lead acetate 25, sodium carbonate 25 

 preparation: Dissolve lead acetate in 6.5 water. Dissolve sodium carbonate in 5 water. 



Mix slowly and with constant agitation with acetate solution. Heat to 35°C. Soak 



gelatin in water. Drain. Melt and mix with load carbonate. 



32.1 Hoyer 1882 2981, 2:19 



formula: water 80, gelatin 20, glycerol 10, silver nitrate 2, 1% pyrogallic acid 2, chloral 



hydrate 2 

 preparation: Soak gelatin in 30 water a few hours. Melt. Dissolve silver nitrate in 50 



water. Mix with gelatin. Add 1 % pyrogallic acid to mixture. Agitate few minutes. Add 



glycerol and chloral hydrate to mixture. 



32.1 Krause 1909 23632, 26:1 



formula: water 2000, sodium borate 100, carmine 1.5, gelatin 100, 2% HCl q.s., 



camphor 0.3 

 preparation: Dissolve carmine in water with sodium borate with boiling. Cool. Chill. 



Soak gelatin in chilled carmine solution 2-3 days. Drain. Rinse. Transfer rinsed sheets, 



with added hydrochloric acid, to solution, 6 hours. Drain. Wash. Drain. Melt. Add 



camphor to molten mass. Cool. 



32.1 MacCallum 1926 590,38:153 



formula: water 30, gelatin 7, carmine 4, ammonia 4 

 preparation: Dissolve carmine in ammonia. Add 20 water. Leave 24 hours. Filter. Boil 



filtrate to volume 10. Add 10 water to reduced filtrate. Again boil to volume 10. Soak 



gelatin in water. Melt. Mix with carmine solution. 



32.1 Moore 1929 4349, 12:55 



formula: water 90, gelatin 25, carmine 6, ammonia q.s., potassium iodide 5, acetic acid 



q.s. 

 preparation: Melt gelatin in 60 water. Soak. Mix carmine in 30 water. Add enough 



ammonia to dissolve carmine. Add potassium iodide to carmine solution. Mix with 



gelatin at 25°C. Add enough acetic acid to give pH 7.2. 



32.1 Robin 1871a Robin 1871, 23 



formula: lard 40, spermaceti 40, beeswax 10, turpentine 15 



32.1 Robin 1871b Robin 1871, 32 



formula: water 60, glycerol 30, gelatin 10, arsenic trioxide 0.5, phenol 0.1 

 preparation: Melt the gelatin in water with arsenic trioxide. Add glycerol and phenol 



to the solution. 

 note: This mass may be mixed with any pigment. 



32.1 Robin 1871c Robin 1871, 40 



formula: water 130, gelatin 15, silver nitrate 30 



preparation: Dissolve gelatin in 100 water with heat. Cool to 30°C. Dissolve silver 

 nitrate in 30 water. Warm to 30°C. Mix with gelatin. 



32.1 Stirling test. Cole 1884 Cole 1884b, 29 



formula: water 50, gelatin 25, acetic acid q.s., carmine 4, ammonia 4 

 preparation: Soak gelatin in water. Drain. Melt. Make to 50. Mix ammonia in 50 



water and carmine. Leave overnight. Filter. Add acetic acid to filtrate drop by drop 



until color changes. Add to molten gelatin. 



32.1 Thiersch 1865 1780, 1:148 



formxtla: water 65, gelatin 15, carmine 10, ammonia 10 



preparation: Mix carmine in 30 water with ammonia. Leave overnight. Agitate. Filter. 

 Dissolve gelatin in 35 water with heat. Add to filtrate. 



