CHEMISTRY. 



139 





with the strength and temperature of the acid. 

 At low temperatures and in weak acid, hydro- 

 gen is given off, and the solution at the end is 

 greenish, containing ferrous chloride; at higher 

 temperatures it is more violent, with the evo- 

 lution of red nitrous fumes and a yellowish 

 resultant solution of ferric chloride. The crit- 

 ical temperature between these two kinds of 

 reaction is at about 40 0. Performing the 

 experiment in the magnetic field, the first re- 

 action, under conditions which would other- 

 wise have insured the evolution of hydrogen 

 only, was marked by an almost immediate and 

 violent outburst of red fumes, accompanied by 

 a correspondingly greater rise of temperature ; 

 and when the reaction was begun with the 

 field in a neutral condition as to magnetism, 

 the mere actuation of the magnet, at any time 

 before the last particle of iron was dissolved, 

 was sufficient to modify it by causing the gen- 

 eration of the nitrous fumes and a more rapid 

 rise of temperature. With nitric acid a per- 

 fectly passive mixture could be brought in- 

 stantly into violent, almost explosive, efferves- 

 cence, with the evolution of the red fumes, by 

 establishing a magnetic connection. With hy- 

 drochloric acid the rise of temperature was 

 much smaller than in the determinations with 

 aqua regia and nitric acid ; and the speed of 

 the reaction differed but little from that oc- 

 curring under ordinary circumstances, while its 

 character in the two cases was almost identical. 



New Substances. Cyclamose is the name given 

 to a new sugar, which is found in the tubercles 

 of Cyclamen Europwum, and the composition 

 of which is expressed by the formula Ci 2 H 22 On. 

 The most striking feature about it is its rota- 

 tory power ( 15'15), which is left-handed ; 

 while all the other sugars in the group Ci 2 H 22 - 

 On are right-handed, or inactive. The activi- 

 ty of cyclamose is not affected by temperature, 

 but it decreases under the influence of basic- 

 lead acetate. Like lactose, it reduces Fehling's 

 solution. 



In October, 1878, M. Delafontaine an- 

 nounced, on the evidence of an absorption- 

 band included in the spectrum of the former 

 erbia, a new earth, philippia. In the begin- 

 ning of 1880 he declared the holmium of MM. 

 Loret and Cleve identical with his philippium ; 

 but later in the same year, finding that the 

 latter body gave no visible absorption-spec- 

 trum, and that the bands which he had at first 

 ascribed to it really belonged to holmium, he 

 renounced this conclusion. M. Lecoq de Bois- 

 baudran has, however, since obtained earths 

 exhibiting distinctly characteristic spectrum- 

 lines, from which he has concluded that the 

 oxide hitherto called holmia is not homogene- 

 ous, but contains at least two radicals. For 

 one of these radicals he proposes to retain the 

 name holmium, while he calls the other one 

 dysprosium symbol, Dy from the Greek dva- 

 Trpoo-iTos, difficult to approach. 



Prof. A. Weisbach has published a descrip- 

 tion of the new mineral argyrodite, in which 



the new element germanium has been discov- 

 ered. It crystallizes in the monoclinic system, 

 with small crystals often united in rounded 

 groups, so as not to allow of exact measure- 

 ment. ' An analysis by Winkler gives as its 

 composition, S 1T13, Ge 6-93, Ag 7472, Fe 

 0-66, Zn 0-22 - 99'66. It occurs as a crust on 

 marcasite and siderite, or again on argentite. 

 The locality is the Himinelfurst mine, near 

 Freiberg. 



Arminite is another name given by Weisbach 

 to a hydrous sulphate of copper found on por- 

 celain-jasper from Planitz, near Zwickau, where 

 it has been formed in the course of the burning 

 of a bed of coal. It forms a green coating, 

 which is resolved by the microscope into short 

 needles or scales. Analyses give results from 

 which is deduced as its probable formula Cu 4 - 

 CaSaOn + 6H 2 O. 



Whitman Cross and L. G. Eakins describe a 

 new mineral which occurs in cavities of a ve- 

 sicular augite-andesite that is found in the con- 

 glomerate of the Green and Table mountains, 

 Colorado. The conglomerate is chiefly com- 

 posed of worn pebbles and bowlders of ande- 

 sitic rocks, embracing various types. Analysis 

 determined its composition to be that repre- 

 sented by the formula EG, A1 2 O S , 10SiO 2 + 

 5H 2 O, K representing CA, K 2 , and No* The 

 substance belongs among the alumino-silicates, 

 of which no previously described hydrate con- 

 tains so high a percentage of silica. The name 

 ptilolite, derived from 7rnXoi>, down, in refer- 

 ence to the light, downy nature of its aggre- 

 gates, is proposed for this mineral. 



Girdwood and Bemrose have determined the 

 existence of a blue coloring-matter which is 

 developed in the decay of the wood of the bal- 

 sam pine (Abies balsamind), which is believed 

 to be the same as the color produced in the 

 reaction of pine-wood with phenol and strong 

 sulphuric acid. Tiemann and Haarman have 

 shown that this is due to coniferin, a substance 

 which has been found in a number of other 

 conifersB, and which, according to Kupel, ex- 

 ists in ah 1 of them. It has also been found in 

 beet-root and asparagus, and is therefore far 

 more general as a product of plant-life than is 

 usually supposed. Samuel Rideal has found a 

 blue coloring-matter, well developed in one 

 specimen, in the decaying wood of the birch, 

 and has subjected it to tests, by which it has 

 been shown that it does not present precisely 

 the same characteristics as that derived from 

 Canada balsam. On carefully testing birch- 

 wood in various stages of growth for the pres- 

 ence of coniferin, no traces of that substance 

 could be found. By other tests the birch-blue 

 was found to differ very considerably from the 

 other natural blue coloring-matters. 



Engel has produced, by the action^ of heat 

 on the double carbonate of magnesium and 

 potassium, a magnesium carbonate having ex- 

 ceptional properties. It is distinguished chief- 

 ly by the facility with which it is transformed 

 into hydrate. Mixed with water, it evolves 



