Notices respecting New Booh. 229 



This table is the most complete that has yet been published. It must 

 be remembered, however, that it includes the products of Boghead and 

 other bituminous shales as well as those of true coals. After the 

 table, is given a brief but sufficient account of the chemical and 

 physical characters of the principal substances mentioned in it. 

 The sketch of the history and properties of benzene is very com- 

 plete, and includes a clear description of the views of its constitu- 

 tion propounded by Kekule, Claus, and Ladenburg. The author is 

 quite right in saying that it would be well-nigh impossible to find 

 one's way through the interminable field of the aromatic compounds, 

 if Kekule's theory of the constitution of benzene had not brought 

 light and order into it. 



Chapter III. is devoted to " The Applications of Coal-tar with- 

 out Distillation.'' It is well written and very interesting, and 

 describes the various attempts that have been made to utilize it for 

 fuel, varnishes, &c. ; it is, however, becoming too valuable for these 

 and similar methods of getting rid of what was once regarded as a 

 nuisance. 



The chapter on the " First Distillation of Coal-tar " is so minute 

 that there is even a section on the " Carriage of Coal-tar." Even 

 the best form of casks is discussed ; and we are informed that 

 •'' Long barrels are said to be pulled more easily than those more 

 bellied." Does the author mean rolled instead of " pulled'' ? The 

 sentence seems rather obscure. The distillation of tar by steam 

 and fire is fully described ; and the best forms of stills, condensers, 

 and rectifying apparatus are illustrated by engravings. 



In treating of Pitch, the manufacture of artificial asphalt, and 

 of the so-called asphalt-pipes used for conveying water, acid, air- 

 blasts, for covering underground telegraph-wires, &c. &c, is de- 

 scribed, and instructions are given for the preparation of artificial 

 fuel. The distillation of pitch for the production of anthracene oil is 

 fully treated ; and engravings are given of Eenner and Versmann's 

 apparatus. 



Chapter VI. is devoted to the working-up of the anthracene oil, 

 which is effected by cooling to cause the solid hydrocarbons to de- 

 posit ; the whole is then pressed, and the liquids are returned to 

 the heavy oils, or employed as lubricants, or are redistilled. The 

 solid portion constitutes rough anthracene, and may be sold as such, 

 or be submitted to further purification. The preparation of anthra- 

 cene has, however, been very fully treated of by Auerbach, whose 

 excellent treatise has been translated into English, and is in the 

 hands of every one interested in the subject. The chapter on Creo- 

 sote oils is a valuable one ; but we think the author is scarcely suffi- 

 ciently alive to the comparatively small part played by phenol in 

 the preservation of wood. Certain it is that long after the phenol 

 has so far disappeared that it is almost impossible to detect it even 

 by the most delicate tests, the wood continues to remain sound for 

 many years. AVe are also of opinion that those modern specifica- 

 tions for creosote oils which insist that no naphthalene shall be 

 deposited at 40 3 E. have been issued under a false impression of 



