1 8 



SCIENCE. 



Anthracite coal, it will be seen contains a very small 

 proportion of volatile matter, and graphite none at all. 

 No two specimens of coal irom different beds or areas 

 are likely to yield upon analysis exactly the same results. 

 This is due to differences in degree and manner of decom- 

 position, the varying degree of metamorphism, the vary- 

 ing impurities, and perhaps a difference in the kind of 

 vegetation. Anthracite coal naturally contains more ash 

 than bituminous, because it is more concentrated, and of 

 course peat has the least proportion of ash, simply de- 

 rived from the inorganic matter of the plant. 



The substance to be described was found in a peat-bog 

 in the city of Scranton during the past summer. It has 

 received attention from the newspaper and scientific people 

 of the eastern coal region of Pennsylvania; and has been 

 recently mentioned in the Am. Jour, of Science for Dec. 

 by a quotation from a letter of,a Scranton gentleman to 

 the Engineering and Mining Journal. 



Scranton lies in the midst of the Lackawanna anthra- 

 cite coal-basin, which forms the northern half of the 

 Wyoming basin. Since the financial panic of 1872 the 

 city has grown but slowly, and a swamp lying in the midst 

 of the city had remained unoccupied, except as an old 

 dumping-ground for cinders from the furnaces. The city 

 having been la'ely made the county-seat of the newly 

 created Lackawanna county, this swamp was selected as 

 the site for a court-house. In excavating for the founda- 

 tions there was found a bed of excellent peat, 10 to 14 feet 

 deep. I visited the excavation and collected specimens 

 from depths of 3, 5, 8, and 13 feet. These specimens, of 

 which a series are before you, were, of course, when fresh 

 and saturated with water, several times their present bulk. 



The peat from the greatest depth was highly decom- 

 posed, or very " ripe." It was fine-grained, close in tex- 

 ture, and although soft held its shape well, cutting like 

 cheese. The color, when freshly cut, was a yellowish- 

 brown, but changed rapidly to a dark-brown, almost black, 

 in a few minutes. Upon drying, the color becomes a 

 lighter or grayish-brown. The rock below the ripe peat 

 is a clayey sand. This is somewhat impervious to water ; 

 but it is likely that beneath it is a more clayey bed which 

 originally held the water and occasioned the swamp. 



In the midst of the ripe peat, termed muck in the let- 

 ter above mentioned, there was found, at various times 

 and at different places, in excavating for the division walls, 

 a substance resembling to the eye a bright coal — anthra- 

 cite if you please. This did not occur in brds or layers, or 

 in any apparent regular manner, but in irregular scattered 

 or branching masses. You will observe in these dried 

 specimens how intimately the coal-like matter and the or- 

 dinary peat are mingled. The two kinds cannot be separ- 

 ated, and it is with difficulty that the dried material can be 

 gotten entirely pure for purposes of analysis. It shrinks 

 upon drying, to a greater degree than the unchanged peat. 

 Masses which I thought would afford fair-sized dry sam- 

 ples have nearly disappeared. The fresh material has 

 been described as a tough jelly, which is perhaps a fair 

 description. It was somewhat elastic, like a mass of soft 

 india-rubber, but would break before bending greatly. I 

 should compare it to a very firm but brittle jelly. The 

 fracture had the lustre of a true coal, and in the dried 

 state the resemblance is perfect. Being found in the 

 midst of an anthracite basin, unscientific people naturally 

 supposed from its associations that whatever bearings it 

 might have upon coal would relate to anthracite coal, 

 not knowing, or not remembering, that anthracite is a 

 metamorphic coal. 



Mr N. L. Brixton, Geological assistant at the School 

 of Mines, New York, has made approximate analyses of 

 this altered peat, from material which I carefuly selected ; 

 also of the peat contiguous to the transformed matter 

 < within the distance of an inch) ; and of the ripe peat from 

 a depth of 13 feet in another part of the excavation. The 

 analyses are of thoroughly and equally drie I samples, and 

 afford the following percentages : 





Moisture at 

 115 Cent. 



Volatile 

 Matter. 



Fixed 

 Carbon. 



Ash. 



1. Ripe Peat 



2. Peat adjacent to 3. . . 



3. Transformed Peat. . . 



6.225 



3-775 

 11.350 



63-875 

 22 125 

 52.800 



4.625 

 4 625 

 24-7*5 



25-275 

 69-475 

 II 125 



4. Transformed Peat. . . 



66.758 



9.826 1 4.012 



19.404 



Number 4 is by the Pennsylvania State Chemist, as 

 published in the American Journal of Science. The 

 moisture is taken at 212 Fahr., and the analysis is evi- 

 dently of the fresh material. 



To obtain a fairer comparison, and if not strictly 

 accurate, yet sufficiently so for our purpose, I have com- 

 puted the percentages with the moisture eliminated. 





Volatile 

 Matier. 



Fixed 

 Carbon. 



Ash. 





68.115 



4 932 



26.953 (White) 



2. Adjacent to 3 



22 993 



4.806 



72 201 ( White) 



3. Transformed Peat 



59-56o 



27.891 



12.549 (Pink) 



4. " (State Chemist) 



29-559 



12.069 



58-372 





30. t j 60. 1 40. to 70. 



3 to 6 



From this table it will be seen that the composition of 

 the transformed peat, number three, is about that of a 

 very " fat " bituminous coal, that is, one containing a 

 large proportion of volatile combustible matter, such as 

 are desired for making gas. In number four, the volatile 

 matter and the fixed carbon have nearly the same propor- 

 tion to each other. 



The very large amount of ash in these samples is to be 

 expected, on account of the small size of the peat-swamp, 

 which allowed much inorganic matter to be blown or 

 washed in over the whole surface. But the varying 

 amount of ash would indicate that the peculiar physical 

 character of the peat was not due to the amount of inor- 

 ganic matter. The ash of numbers one and two was white, 

 while that of number three was decidedly pink. This color 

 probably indicates iron ; which may possibly afford a clue 

 to the cause of the transformation. The presence of con- 

 siderable iron either inherent in the mass itself, or derived 

 from the surrounding mass by something like concretion- 

 ary action would probably hasten the decomposition ; 

 bearing upon this point, the large amount of inorganic 

 matter without iron in the peat contiguous to the trans- 

 formed peat is remarkable. The physical characteristics 

 are undoubtedly due to the finely divided state of the car- 

 bon, mingled with the water and volatile matter. But, 

 however produced, we have here something that is appar- 

 ently coal, in the midst of peat that is not yet coal. 



Except as this substance illustrates a degree or phase 

 of peat decomposition, it is not likely to have any bearing 

 on the formation of coal. The decomposition of a buried 

 peat, bed under great pressure probably involves the whole 

 mass at the same time, and does not proceed by the ex- 

 pansion of such centres of decomposition as are here 

 found. 



Samples have been placed in the hands of Mr. Spencer 

 B. Newberry, of Cornell University, who is making a 

 full chemical examination. 



DISCUSSION. 



Dr. L. ELSBERG then said that some 20 years ago he was 

 engaged in experiments on the subject of converting peat 

 into coal by a more rapid process than that occuring in 

 nature. He found that moisture, heal and pressure were, 

 as he supposed, the elements which, together with time, na- 

 ture had employed ; and these three factors could and can 

 be used really to make a very good coal. On some future 

 occasion he would bring specimens of the manufactured 

 coal and of various kinds of coal to the Academy, and 



