214 Scientific Intelligence. — Arts. 



riments to produce a durable ink from metallic combinations, 

 stated that he was induced to attempt the composition of a car- 

 bonaceous liquid which should possess the qualities of good 

 writing-ink. The inks used by the ancients were carbonaceous, 

 and have admirably resisted the effects of time ; but the author 

 found that the specimens of writing on the Herculaneum and 

 Egyptian papyri were effaced by washing with water ; and on 

 forming inks after the descriptions of Vitruvius, Dioscorides, 

 and Pliny, he found that they did not flow freely from the pen, 

 and did not resist water, — qualities essential to a good writing- 

 ink in modern practice. The carbonaceous inks with resinous 

 vehicles, rendered fluid by essential oils, though they resisted 

 water and chemical agents, had the disadvantages of not flow- 

 ing freely from the pen, and of spreading on the paper, so as 

 to produce unseemly lines. Solutions of caoutchouc in coal- 

 naphtha, and in a fragrant essential oil, lately imported from 

 South America, under the name of aceite de sassafras (the na- 

 tural produce of a supposed Laurus), were subject to the same 

 objections. The author tried various animal and vegetable 

 fluids as vehicles of the carbon, without obtaining the desired 

 result, until he found, in a solution of the gluten of 

 WHEAT IN PYROLiGNEOus ACID, a fluld Capable of readily unit- 

 ing with carbon into an ink, possessing the qualities of a good, 

 durable, writing ink. To prepare this ink, he directs gluten of 

 wheat to be separated from the starch as completely as possible, 

 by the usual process, and when recent to be dissolved in pyro- 

 ligneous acid with the aid 'of heat. This forms a saponaceous 

 fluid, which is to be tempered with water until the acid has the 

 usual strength of vinegar. He grinds each ounce of this fluid 

 with from eight to ten grains 'of the best lamp-black, and one 

 and a half grain of indigo. The following are the qualities of 

 this ink. 1. It is formed of cheap materials. 2. It is easily 

 made, the colouring matter readily incorporating with the 

 vehicle. S. Its colour is good. 4. It flows freely from the 

 pen. 5. It dries quickly. 6. When dry it is not removable 

 by friction. 7. It is not affected by soaking in water. 8. Slips 

 of paper written on by this ink have remained immersed in so- 

 lutions of chemical agents, capable of immediately effacing or 

 impairing common ink, for seventy-two hours, without change, 



