204 Peckham and Linton — Trinidad Pitch. 



ance. The word glance is from the German word "glanz,' r 

 which means glistening. Pure asphaltum that has been 

 melted has a smooth glistening fracture like rosin or anthracite 

 coal. It would be impossible to produce glance pitch by 

 melting a material containing so much mineral matter as Trin- 

 idad pitch. Iron pitch is the nearest approach to it that can 

 be found in the neighborhood of the Pitch lake, and that was 

 found both within and without the lake. If it has been 

 intended to convey the impression that asphaltum becomes 

 glance pitch by aging, and that the land pitch is farther on 

 the way through geological time towards glance pitch than 

 that in the lake, it must also be admitted that so far as anyone 

 knows to the contrary the whole phenomenon of the pitch 

 lake may have been produced within five hundred years. Our 

 analyses have not furnished the slightest evidence that the 

 bulk of the pitch outside the lake has aged any more than that 

 within it. Our analyses also show that the bulk of the pitch 

 is in good condition throughout the deposit ; and that the 

 effects of aging are about equally distributed. 



These analyses do not sustain the allegation that land pitch 

 is any less uniform in composition than lake pitch. The fol- 

 lowing figures represent the extremes in the percentage com- 

 position of total bitumen in the five samples of commercial 

 lake pitch and the five samples of commercial land pitch 

 soluble in 



Land. Lake. 



Petroleum ether.. _ 3*445$ 3-601 



Boiling spirits turpentine 9*746$ 7*110 



Chloroform 9*622$ 9*716 



Total soluble in turpentine. .. 9*621$ 9*696 



The correspondence between them is remarkable. 



It makes no difference whether these results of analysis are 

 taken as a whole, or compared severally, or in the different 

 elements that make up each analysis, the same conclusion is 

 inevitable, viz : that the entire deposit both within and with- 

 out the boundaries of the lake is one and the same substance 

 and in substantially the same condition. 



There are five specimens in the collection that represent the 

 rubbish of the deposit. Nos. 3 and 18 are respectively land 

 and lake " iron-pitch," Nos. 11 and 13 are decomposition prod- 

 ucts from the land and lake respectively, that may be what has 

 been called " chocolate pitch," No. 12 may be what has been 

 called "grey pitch." None of these are commercial articles, 

 yet they are shown by these analyses to have scientific rela- 

 tions to the commercial pitches full of interest. By compar- 

 ing these five specimens with any other five in the tables, it 

 will be found that they are low in material soluble in petro- 



