I have exhausted my browning reagent supply. But I have a good recipe from Angier's book, and the chemistry prof at our local university is mixing me up the acid solution. Here's the recipe for anyone who wants an excellent browning solution:
2 1/2 oz Nitric Acid
2 oz Hydrochloric Acid
Add 1 oz iron nails (I use hay wire)
Mix in 30 oz distilled water.
Many years ago, while visiting my buddy in Marysville, BC, I met his next door neighbour. Wendell McLeod, who was a gunsmith tinkerer, and he gave me a vanilla bottle full of this mixture. What a great browning solution!! But I ran out, so thankfully, he gave me the recipe.