— 134 — 



It will be seen that this method of producing oil yields a product 

 which, in the most favourable case, deserves to be described as "wood 

 turpentine". 



Among the other information given by De Lapasse is the interesting 

 statement that, so far, the attempts to introduce the "cup-and-gutter 

 system" (see below) into the United States have encountered the hostility 

 of the coloured labourers, who refuse to abandon the rough-and-ready 

 "box" method for the careful manipulations required by the French method. 

 As an example of their carelessness it is stated that when lengthening the 

 incisions in the tree, they neglect to cover the cups for the collection 

 of the gum, with the result that the latter is contaminated with particles 

 of wood and bark, and in consequence yields an inferior rosin. 



The repeated attempts on the part of the Federal Authorities of the 

 United States to induce those interested in the industry to abandon the 

 ruinous boxing- method and to adopt in its place the less exhausting 

 cup-and-gutter system 1 ), appear, according to an American periodical 2 ), 

 at last to have had the result that the Executive Committee of the 

 Consolidated Naval Stores Company has declared itself against the 

 continuance of the old method in every shape and form and in favour of 

 the introduction of the cup-and-gutter system. The said Committee, in 

 announcing this decision, bases it expressly upon the various experiments 

 carried out by the Government, which have established the superiority of 

 the new over the old system without any doubt. 



In our last Report 3 ) we referred in detail to a paper by Marcusson on 

 the methods at present known for detecting foreign additions to turpen- 

 tine oil. Marcusson came to the conclusion that the well-known sulphuric 

 acid test does not give absolutely trustworthy results in the detection 

 of hydrocarbons of the benzene series, and indicated his preference for 

 the nitric acid process, which he has modified in some respect. The 

 criticisms to which Herzfeld 4 ) subjected Marcusson's statements caused 

 the latter 6 ) to repeat his experiments. He then again found, as he had 

 done before, that additions of 10% benzene to an oil of turpentine are 

 not, or only exceptionally, traceable by adding to the portion of the oil 

 which remains insoluble in three times the volume of sulphuric acid. 

 Even mixtures of equal parts of xylene and turpentine oil never left a 

 greater residue than did the pure oil alone. Marcusson cites Bohme 6 ), 



*) Comp. Report April 1906, 65; October 1909, 114, 116. 



2 ) Oil, Paint and Drug Reporter 77 (1910), No. 18, p. 28 E. 



3 ) Report April 1910, 109. 



4 ) Comp. Ibidem p. 114. 



5 ) Chem. Ztg. 34 (1910), 285. 



6 ) Comp. Report October 1906, 77. 



