P OP ULAR MIS CELL ANY. 



429 



is distilled. This spirit, as prepared from 

 various grains, fruits, beet-roots, etc., is 

 produced in many qualities, each of which 

 acquires some special and relatively disa- 

 greeable flavor from whatever article has 

 been subjected to distillation ; and the al- 

 cohols are therefore classified in the arts 

 according to the sources from which they 

 are derived, and subdivided into those of 

 " good taste," " middling taste, and " bad 

 taste." Other alcohols are found along 

 with the vinous alcohol in fermentation, 

 but, as a rule, they do not materially affect 

 its taste. The case is different with the 

 aldehydic or acetonic bodies that are pro- 

 duced, whose pronounced and disagreeable 

 taste is obstinately persistent in rectifica- 

 tion. The methods which have hitherto 

 been employed to take away these tastes de- 

 pend on oxidation ; this acts, however, upon 

 the alcohol itself, and generates odorous 

 ethereal substances which only give another 

 bad taste instead of the original one. No 

 better results have been obtained with other 

 substances that have been recommended, 

 including potash, soda, oil, fat, soap, and 

 sodium. M. Naudine has adopted a course 

 which has been suggested by the fact that 

 hydrogen, in a nascent state, converts the 

 acetones into secondary alcohols. His meth- 

 od consists in the subjection of the alcohol 

 to be purified to the action of the Gladstone 

 and Triber reducing pile, or a similar bat- 

 tery, whereby hydrogen is developed and 

 acts immediately upon the impurities of the 

 spirit. 



Speed of Explosives. M. Berthelot has 

 been investigating the speed with which ex- 

 plosive phenomena are propagated in gases. 

 For this purpose, he filled with the explo- 

 sive mixture of oxygen and hydrogen, car- 

 bonic oxide, and oxygen under atmospheric 

 pressure, an iron tube about sixteen inches 

 long and a third of an inch in bore, so ar- 

 ranged that the passage of an explosive 

 could be accurately registered at a point close 

 to where the spark was applied, at the mid- 

 dle, and at the farther end of the tube. The 

 experiment showed the speed of propagation 

 to be about twenty-five hundred metres 

 (8,125 feet) a second. The results should not 

 be regarded as furnishing the absolute value 

 of the speed of the explosive force, for the 



quantities measured are too small for that ; 

 but they at least give an indication that the 

 speed is much greater than had been sup- 

 posed. Bunsen, for example, in 1S67, had 

 estimated it at thirty-four metres a second 

 for detonating gas, and one metre for car- 

 bonic oxide mixed with oxygen. The rapid 

 propagation of explosive phenomena ap- 

 pears to be due to the transmission of the 

 successive shocks of the gaseous molecules, 

 which have been brought into a vibratory 

 condition more intense than the heat dis- 

 engaged in their combination. The phe- 

 nomena of explosion are, then, more com- 

 plex than a simple movement of transmis- 

 sion, or even than the propagation of a 

 sonorous wave. 



Fossilized Standing Trees. M. Fayol 

 has observed fossilized trees standing per- 

 pendicular to the planes of stratification of 

 the beds that contain them, in the coal- 

 measures of Commentry. In the bed of 

 Boseaux the trunks are so numerous as to 

 resemble a fossil forest. The standing trees 

 are fragments of trunks, without branches 

 or roots, and occur generally in the grits, 

 occasionally in the conglomerates, rarely in 

 the shales, but not in the coal-beds. Pros- 

 trate trees are numerous in the shales, less 

 abundant in the grits, and rare in the con- 

 glomerates, while numerous traces of them 

 may be distinguished in certain parts of the 

 coal-beds. The prostrate trees are a hun- 

 dred times more numerous than the stand- 

 ing ones, and are found almost everywhere 

 in the beds. These facts may be explained 

 as the results of a transporting movement. 

 A recently pulled-up plant, when thrown in 

 the water, stands vertically, then sinks to 

 the bottom in the same position, and after- 

 ward falls prostrate, remaining in each po- 

 sition for some hours or even days. If the 

 trees were carried by the current to a lake 

 or estuary, they would, according to the 

 condition they were in, either float around 

 for a while or sink at once, and would be- 

 come fossilized in the position they took. 



Disinfecting Powers of Sulphnrons Acid. 



Dr. Victor Fatio, of Geneva, has made a 

 series of interesting experiments on the dis- 

 infecting power of sulphurous acid, par- 

 ticularly with reference to the destruction 



