[809] Mixing Lampblack with Water.

Manufacturer and builder 11, 1873

We found that the use of alcohol always helped us out of this trouble. When once mixed with strong or diluted alcohol (with which it mixes very readily) into it paste, it will suffer the addition of any amount of water without floating on it. This is however expensive if mixing large quantities. In this case it is cheaper to follow Kochlin's method; he uses for every pound of lampblack ten pounds of sulphuric acid of 66° Beaum spec. gr. This penetrates readily through all the lampblack. He lets it stand for several hours, then he adds water, which will readily unite with the sulphuric acid. The mass is then placed on a filter, and water percolated till all the acid is washed out when it is changed into a black paste, which when dry is nearly identical with good India ink, and will easily mix with water any time afterward.