230 ANNUAL OF SCIENTIFIC DISCOVERT. 



Thymic Acid. — This acid, obtained from the essential oil of 

 th3me, has been proposed as a succpdaneuni of carbolic acid or 

 creosote. It emits no disagreeable smell, and is powerfully anti- 

 septic. Its composition is C20H14O2. In a concentrated form it 

 may take the place of nitrate of silver; and, as an antiseptic, it 

 shoidd be dissolved in 1,000 parts of water, with the addition of a 

 little alcohol. 



New Alloys of Lead and Tin. — Two new alloys are described, 

 containing less tin tlian ordinary pewter, which are not acted 

 upon by boiling acetic acid or by salt water, and may therefore be 

 used for some kinds of utensils. The first alloy contains 1 part 

 of tin and 2.4 parts of lead. It has a density of 9.64, and melts 

 at 320° F. It is made by first melting the lead, and, after skira- 

 111 lug it, adding the tin, by stirring it constantly with a wooden 

 stick. In the mean time the lead is prevented from settling to 

 the bottom. The second alloy consists of 1 part of tin with 1.25 

 of lead. It is less mallealde and more brittle than the first. 



Artificial Magnetic Oxide of Iron. — M. Sidot has communicated 

 to the Academy of Sciences a paper " On the Artificial Production 

 ot Magnetic Oxide of Iron." This he does by introducing a small 

 platinum disk, filled with colcothar, into a porcelain tube, situated 

 in a direction parallel to that of a dipping-needle. After keeping 

 the tul)e at a temperature a little below a white heat for about an 

 liour, the colcothar will be found transformed into a grayisli 

 metallic oxide, the particles of which are strongl}- agglomerated 

 together. This mass possesses the property of polar magnetism. 



Action of Colored Bays on Plants. — An examination of the tabu- 

 lated results obtained by M. Cailletct shows that the calorific rays 

 as well as the chemical rays are without action on the dissociation 

 of carbonic acid by plants. It would seem, from an inspection of 

 these results, that the colors the most active in a chemical point 

 of view (in regard to tlie coloration of chloride of silver, for ex- 

 ample) are those which favor the decomposition of carbonic acid 

 the least. Yellow induces the largest decomposition, and red 

 next ; violet and blue affect it but little. With green light, whether 

 from the color contained in vegetables, or from solutions or colored 

 glass, the action is peculiar. Under this influence the decomposi- 

 tion of the carbonic acid is nil ; a nevv quantity of this gas is, on 

 the contrary, produced by the plants. 



Bhcedine. — A new alkaloid, named rhaedine, has been dis- 

 covered by Hesse, in the red popi)y and in opium. It is soluble 

 in water, alcohol, and ether, crystallizing from the last in white 

 prisms. Ammonia precipitates it in white crystalline flocculi, 

 bichloride of mercury gives a white amorphous precipitate, chlo- 

 ride of gold a 3-ellow precipitate, and strong acids decompose it in 

 the gold, giving a purple solution. 



Tiers-Argent. — This beautiful wiiite alloy consists of two-thirds 

 aluminium and one-third silver. It is now made perfectly homo- 

 geneous, and is easily fabricated. Its hardness and lightness are 

 valuable qualities in table furniture. Spoons, forks, goblets, and 

 stilvers, made of this material, are rapidly coming into use in 

 Paris. 



