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slo"^', the leaves not attaining their maximum temperature until 9 o'elock 

 p. m. Tims, while the atmospheric changes are rapid, the temperature 

 varies slowly in the trees, and therefore they serve, like the ocean, as 

 equalizers of the temperature, moderating the heat of the day and 

 maintaining a higher temperature during the night. 



In continuation of the same subject, Mr. Buchan remarks that, as 

 air is heated by contact with the soil, and as trees shelter the soil from 

 the solar radiation, they must diminish the force of the sun's rays, espe- 

 cially in the lower strata of the atmosphere. The exhalation of moist- 

 ure by trees produces cold in the air by abstracting the latent heat from 

 it. This lowering of the temperature gives to the air a greater degree 

 of humidity. Again, the leaves of trees exercise an important influence 

 in cooling the atmosphere, as the tree itself, by its radiation of heat, 

 becomes sensibly lower in temperature, and thus cools the air as it plays 

 among the leaves. 



ViNEGAK FROM UNEIPE PRUTT. — Unripe fruit, especially apples and 

 pears, as is well known, is much used in the manufacture of vinegar; 

 but the process usually adopted is defective in many important points. 

 We therefore give, for the benefit of our renders, the substance of an 

 article from Graeger's Manual of Vinegar Making, just published in 

 Germany, which may, perhaps, serve a useful purpose. The principal 

 fault of the old process consists in throwing away the pulp after the 

 juices are expressed. As this, however, contains a large percentage of 

 starch, excellently adapted for conversion into vinegar, it is necessary 

 to prepare the fruit so as to save this portion of its substance. With 

 this object it is to be grated, exactly as potatoes are prepared in the 

 manufacture of starch, and the pulp passed through a moderately fine 

 sieve, or through a coarse and open meshed cloth. There is thus noth- 

 ing left behind but the pomace proper, or cellulose, all the starchy matr 

 ter having been passed through the sieve -with the juice. This is next 

 to be diluted with water, in proportion to the quantity. of starchy mat- 

 ter thus obtained; and the whole is then placed in a clean copper 

 kettle, one or two per cent, of concentrated sulphuric acid being added, 

 and heated long enough to transform the starch into grape sugar. The 

 sulphuric acid is to be neutralized by means of carbonate of lime ; the 

 gypsum or the sulphate of lime thus produced allowed to settle, and the 

 liquid to become clear, and then poured oft". This liquid is to be left for 

 fermentation to take place, either with or without the use of yeast. A 

 liquid having 8 or 10 per cent, of sugar can easily be made to have 

 4 or 5 per cent, of alcohol after fermentation, which, by its subsequent 

 acidification, will yield a vinegar of 5 to 6 per cent, of acetic acid. 



Use of flesh or milk of aphthous cattle. — Professor Dammann 

 has lately renewed, with great care, the inquiry as to the wholesomeness 

 of flesh or milk of cattle that have been afflicted with the foot and 

 mouth disease, and has come to the conclusion that the use of these 

 substances cannot be forbidden with sound reason. He states tliat the 

 flesh is absolutely harmless, and its use should be allowed under any 

 circumstances, taking care iu ever^^ case that the slaughtering be done 

 in one and the same place, in order that no new locality be unnecessarily 

 tainted by the liquids resulting from the operation. 



In reference to using the milk, he states that should any misgiving 

 be felt, it may be converted into butter or cheese, in which case it is 

 absolutely harmless. No reliable instances could be found, in the course 

 of a long and careful inquiry, of any infection or disease having been 

 communicated to mankind or the lower animals by eating the ilesh of 



