210 Miscellanies. 



corides, 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 vehi- 

 cles, rendered fluid by essential oils, though they resisted water and 

 chemical agents, had the disadvantages of not flowing 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 natural produce of a supposed Laurus,) were sub- 

 ject to the same objections. The author tried various animal and 

 vegetable fluids as vehicles of the carbon, without obtaining the de- 

 sired result, until he found, in A solution of the gluten of 

 WHEAT IN PYROLiGNEOUS ACID, a fluid capable of readily uniting 

 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 pro- 

 cess, and when recent to be dissolved in pyroligneous 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 coloring matter readily incorporating with the 

 vehicle. 3. Its color 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, having remained immersed in solutions of chemical 

 agents, capable of immediately effacing or imparing common ink, for 

 seventy-two hours, without change, unless the solutions be so concen- 

 trated as to injure the texture of the paper. The author offers this 

 composition as a writing-ink, to be used on paper, for the drawing 

 out of bills, deeds, wills, or wherever it is important to prevent the 

 alteration of sums or signatures, as well as for handing down to pos- 

 terity public records, in a less perishable material than common ink. 

 He concluded his paper by stating, that should it be found to present 

 an obstacle to the commission of crime — should it, even in a single 

 instance, prevent the perpetration of an offence so injurious to soci- 

 ety, as the falsification of a public or private document, the author 

 will rejoice in the publication of his discovery, and consider that his 

 labor has not been in vain — lb. 



39. Depth of the Frozen Ground in Siberia. — " At page 435 of vol. 

 24th of Edinburgh New Philosophical Journal, we inserted Profes- 



