1837] 



FARMERS' REGISTER. 



399 



two countries eiijoj'' the Piiine temperature, they 

 present nearly I lie same purliice, and liavc a like 

 l)osilion relatively the mounlains. 



M. Arago remarks that a contrary result lias 

 been observed at Viviers, in tlie department of 

 Ardoehe, where the quantity of rain fallen has 

 augmented since the clearing ot* the forests from 

 the country. 



On the other hand, M. Deveze of Chabriol has 

 come to the conclusion, li-om the examination of 

 several historical documents, that in the depart- 

 ment of Carilal, in the environs ol' Saint Flenr, 

 there has been an abatement of temperature since 

 the disappearance of the forests. For example, 

 from the records of the 13ih and 14th centuries, it 

 is proved that at this period the vine was cultiva- 

 ted on the slope of the hill of Saint Fleur, and this 

 culture will not succeed at present. The chestnul 

 has also disappeared- from many of the cantons 

 where it formerly flourished; and many villages 

 situated near the summits of mountains have been 

 abandoned. It is also remarked that, in this coun- 

 try, man\^ streams have been dried up, in conse- 

 quence of the clearing of the forests. 



PURIFICATION OF TAR. 



Tar contains a certain quantity of pyroligneous 

 acid from the wood which produces it, and which 

 in time occasions the destruction of cordage by 

 thickening, in the manner of pitch, as soon as the 

 oily portions have disappeared. This change pre- 

 vents the threads from stretching, and of course 

 they must break, although they may siill be sound. 

 The acid should iherelbre be carefully extracted 

 from the tar. This is effected by washing it in 

 clean lime-water. They are to be well agitated 

 together in any suitable reservoir,' by a convenient 

 instrument of any kind, changing the lime-water 

 Irequenlly, and continuing the operation until a 

 good test paper indicates a freedom from all acidity. 



Tar thus purified is a good preservative of wood, 

 which it defends from decay much longer than 

 common tar, because the. acid attracts moisture 

 from the air, and reiains^ it in the fibres of the wood; 

 but purified tar repels moisture, and thus acts as a 

 preservative. — Jour, des Conn. Usuelles. 



From tlie British Farmer's Magazine. 



MANUFACTURE OF BEET-ROOT SUGAR IN 

 FRANCE. 



From the French of M. Duhi uirfaiit and others. 

 [Continued from p. 91] * 



CHAP VI. 



Concentration of the Juice. 



. If after defi^cation, the juice were only a cryslal- 

 lizable matter, composed but of liquid sugar and 



* The delay of our continuation of this article has 

 been caused by the miscarriage of the No. of the Eu- 

 ropean journal, next in order, from which we copy. If 

 the loss had been total, we should not only have been 

 placed in the disagreeable position of commencing an 

 article without being able to complete it, but, unwit- 

 tingly, had seduced sundry of our brethren into the like 



water, all that would be necessary could be accom- 

 plished by evaporation. Hul this is not the case, 

 ii)r when the juice is subniiited to tliis operation, it 

 soon becomes turbid, I hough clear at first, and 

 presents to the eye a number of lumps similar to 

 those produced by delineation, and which are held 

 in solution, and only f)recipitaied as the wafer 

 evaporates. These solid particles contribute to 

 the alteration which takes place in the sugar. One 

 inconvenience attendiuir them is this: ihat if it 

 were wished to proceed at once to boil the juice 

 without iiilerposinfj between the defncalion and 

 this same boiling, some process by which the syr- 

 up can be purged fi'om the imjiurities which are 

 held in suspension in it, we should obtain nothing 

 but a thick substance which would burn beliire it 

 perfected its sugar, and from which, in fiict, not an 

 atom of crystallizable matter could be extracted. 

 It is this circumstance which dislin<ruishes, in beet 

 root su(jar works, concentration fi'om boiling ; oth- 

 erwise these two operations have the same end in 

 view: namely, the s(>paraiion of the water from 

 the juice by evaporation. The. difference between 

 them in the order of the proceedin<Ts is — 1. That 

 concentration precedes ooiling. 2. That the one 

 operates on larger Inxiics than the other. 3. That 

 the process of clarification intervenes, the object of 

 w'hich is to separate the substances precipitated by 

 concentration, iri order to produce a clear, limiiid 

 juice fJir boilinir. 4. That the concentration takes 

 ihejuice at the density of defi^caiion to carry it to 

 20 or 25° hot, while boiling takes it at this density 

 to carry it to 40 or 41° (areometrical,) a point near- 

 ly sufficient for a good crystallization. 



The process of deiin^ation generally causes a 

 loss in the weight of the raw juice of 1° or 1-|°; for 

 instance a juice that weiglied 7 areometrical de-- 

 grees at 10° (55°) of the thermometer, would not 

 weigh, after defecation, more than about 6°. If it 

 weighed 10° the defecation would reduce it to 8^°; 

 in fiict the loss ol' weight in this case is nearly it> 

 proportion to the density of the juice. 



difficulty; for nearly all the editors of agricultural pa-- 

 pers in this country have copied the commencement 

 from the Farmers' Register, relying of course upon 

 this journal for the means to furnish to tlieir readers the 

 conclusion. So far as we know and believe, the copy 

 of the British journal from which we take this piece 

 is the only one received in the United States. And 

 therefore, if we had remained under the privation of 

 the loss of the continuation, all those who have profit- 

 ed by our provision in this matter, woTifd have been 

 placed in the same awkward predicament. 



No pains and expense have been spared, on our part, 

 to obtain the best foreign agricultural periodicals, 

 and other new agricultural works; and yet none of our 

 elForts have been attended with more disappointment. 

 Delays in receiving new publications are generally en- 

 countered, and total losses frequently, and we pay for 

 all lost packages, as well as all received. And after 

 all the cost, and the trouble added of selecting articles 

 from the m^ss of worthless matter, the pieces so select- 

 ed are copied into other agricultural journals of this 

 country, and generally without the slightest acknowl- 

 edgment of the source whence they are immediately 

 derived. — Ed. Far. Reg. 



