Scientific Intelligence, — Natural History. 165 



fossil wood, discovered near Urnacli, in the canton of St. Gall ; and 

 being given to M. Macaire Prinsep, he has examined and published 

 an account of it. It occurs in small white, or yellowish white acic- 

 ular crystals, between the fibres of the fossil wood, or else in trans- 

 lucent layers, having a nacreous lustre, no taste or smell, and a spe- 

 cific gravity of about 0.65.* 



Heated, it fuses, and remains liquid when cooled, until touched, 

 when it suddenly crystallizes. It melts at 112° F., distils at 194° F. 

 and condenses unaltered. It sinks in alcohol at 40°, (s. g. .867 ?) 

 dissolving only slowly, unless heat be applied. It dissolves in ether 

 and oil of turpentine, not in water or alkaline solutions. It differs 

 from naphthaline in being more fusible, more volatile ; in the form 

 of its distilled product, which, with naphthaline, is frequently that of 

 rhomboidal plates j in its inferior solubility in alcohol, and also as it 

 appears in composition. 



M. Macaire Prinsep analyzed both naphthaline and tlie substance, 

 by the use of peroxide of copper ; but appears to have doubts, not 

 of the principle of the process, but of his results. However, he 

 makes out naphthaline to consist nearly of 86 carbon, and 13.8 hy- 

 drogen ; this is almost equal to single proportionals of each, or 6, 

 and 1 by weight, which is the composition of defiant gas ; but both 

 Ure and Thomson make out far less of hydrogen. 



The new fossil is, according to M. Macaire Prinsep, composed of 

 73 carbon, and 24 hydrogen, or nearly of one proportional of car- 

 bon to two of hydrogen j 6 : 2 by weight. This is the same compo- 

 sition as the Hght hydro-carbon. (Bull. Univ. xl. 68.) 



If the latter estimate be at all near the truth, then it would be ex- 

 ceedingly interesting to know the specific gravity of its vapor, for 

 comparison with light hydro-carbon ; and also the kind of flame 

 which is produced when the vapor of the substance is burnt from a 

 jet. No indication of the appearance of the flame, whether pale, 

 bright, or smoky, is given. — Ed. Quar. Journal, No. x. 431. 



4. Means employed by the spider in iveaving its web. — We find, 

 in the introduction to Entomology by Kirby and Spence, a very cu- 

 rious description of the means employed by spiders in warping their 

 webs. The author, after having described the four little spiders, as 



* There must be some mistake here, for afterwards it is said to sink in alcohol. 



