CHEMICAL SCIENCE. 215 



evidence. He has -painted over six thousand public and private estab- 

 lishments, the Departments of War and of Public Works, the 

 Bank of France, the Prefecture of Police, the railroad depots, &c., 

 and in every instance the fact is conclusively established, that the 

 colors, with their bases of zinc, manganese, &c., are by no means in- 

 jurious to the health of the workmen engaged in their manufacture, 

 to painters using them, or to the persons who may reside in houses 

 freshly painted. Of the correctness of this statement it is only neces- 

 sary to say that, under the old order of things, a dozen of M. Le- 

 claire's workmen, on an average, were attacked yearly by this un- 

 pleasant disease; whereas, now, not a single person in his employ 

 has been poisoned. The new colors are infinitely more solid and du- 

 rable than the old ; they preserve everywhere and always their 

 primitive tints, even in sulphuric bath-rooms ; and they have a property 

 still more precious, namely, when they are cleansed by simple wash- 

 ing, they resume their original brightness, while the old colors, when 

 washed even with acids, which dissolve a portion, remain dull and 

 spotted, and for the simple reason, that every thing which decomposes 

 stains them.- The white of zinc is so much superior to the white of 

 lead, that when the framing of a panel is painted with the best white 

 lead and the centre with zinc-white, the contrast makes the framing 

 look yellow and gray and offensive to the eye. In such a comparison, 

 even the Venetian white loses its purity. The white lead appears to 

 absorb the light, while the white of zinc reflects it completely, and is 

 brilliant and transparent. The new colors are much richer and bright- 

 er, are easily applied, and dry in a very short time. They are also 

 more economical, for experience has fully proved, that, if we compare 

 the quality of white of lead with the white of zinc, or the quantities 

 of oil necessary to prepare these two substances, the advantage of at 

 least thirty per cent, is in favor of the white of zinc, which covers 

 better with equal weight. 



M. Leclaire has received the Cross of the Legion of Honor, as a 

 reward for his discovery. 



DEODORIZING POWERS OF PEAT CHARCOAL. 



AT a meeting of the Mechanics' Institute, in London, several ex- 

 periments were tried, having for their object the exhibition of the de- 

 odorizing powers of a species of charcoal prepared from Irish peat. 

 In one of the experiments a pan of night-soil w r as put in a hopper 

 along with two pans of peat charcoal. The mixture was then ground 

 in an ordinary hand-mill, and delivered into a vessel, where it was ex- 

 amined by many scientific men, who all agreed in considering the ex- 

 periment successful, as they could not detect the least disagreeable 

 odor. One of the inspectors of the Board of Health stated that this 

 charcoal would afford an admirable means of disinfecting cesspools. 

 A gentleman also stated, that he had tried its effect with complete 

 success on various kinds of manure. Mr. Rogers, the inventor, re- 

 marked that he had given unremitting attention to the subject for five 

 years, and that he could deliver, in London, the coal made from Irish 

 peat at about twelve dollars the ton. 



