M. H. Rose on a new Series of Metallic Oxides. 363 



applied. In such instances the fragments of glass, emery, or 

 sand are so loosely attached that a great proportion may be 

 removed by passing the finger lightly over them. It is evident 

 that, in packing match-boxes of this kind, much of the frictional 

 powder will become detached, and further quantities will speedily 

 be rubbed off and be loose in the cases if the slightest play for 

 movement of the boxes during transport exists in the packages. 

 The hard angular particles thus liberated will speedily insinuate 

 themselves into the boxes and between the matches ; and it is 

 self-evident that they may then contribute their share towards 

 augmenting the possibility of accident. 



It is almost needless to mention that the foregoing remarks 

 do not in any way refer to the matches spoken of in the begin- 

 ning of this communication, which are ignited only by being 

 passed over a surface of their box which is coated with a prepa- 

 ration of amorphous phosphorus. The compositions with which 

 the matches of this class are tipped require very powerful fric- 

 tion or percussion for their ignition, and are of course inflamed 

 at temperatures far above that required to ignite the least sensi- 

 tive of the matches prepared with phosphorus. The possibility 

 of their accidental ignition must therefore be, to say the least, 

 extremely remote. 



In conclusion, it may be asserted with little hesitation, that no 

 difference of opinion is likely to exist regarding the compara- 

 tively very great risk which must be incurred in the transport of 

 the new varieties of cigar lights, and, indeed, the impossibility of 

 adopting precautionary measures which can warrant their ship- 

 ment with any confidence in the safety of the vessel. 



LII. On a new Series of Metallic Oxides. By H. Rose*. 



BERZELIUS determined, by numerous and variously mo- 

 dified experiments, the atomic weights of the simple sub- 

 stances, paying especial regard to the analogous properties of 

 their oxides, in which he evinced wonderful circumspection and 

 a fine tact. With the greatest care he took into consideration all 

 circumstances ; so that his assumptions, with few exceptions, 

 could be recognized as being correct, even when, after the dis- 

 covery of two very important laws, it was possible to determine 

 the atomic weights of the simple bodies with greater certainty 

 than before. One of these laws is that discovered by Dulong 

 and Petit, that the specific heats of the simple bodies are in- 

 versely as their atomic weights. This law has been especially 



* Translated from PoggendorfPs Annalen for September 1863., by Dr. 

 Atkinson, Roval Military College, Sandhurst. 



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