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very great. Donald Stuart, who examined this part of the country, 

 under the direction of the Royal Dublin Society, states that a fruitless 

 search for coal was made in this quarter, at Portmore. They bored 

 through two beds of coal, or what is called black wood, twenty-five feet 

 thick each, and a third stratum, nine feet thick, and eighty yards 

 deep. They bored eighteen inches deep, into a fourth stratum, having 

 no more rods to go deeper.'' 



If we travel along the shores of Lough Neagh, from Cranfield, on 

 the north, to the parish of Seago, in Armagh, on the south, we observe 

 the silicified wood at the mouth of the Glenavy river ; thence, three 

 miles inland, at the village of Glenavy. "We also find it in the Crumlin 

 River, at an equal distance from the lake ; also, at Langford Lodge ; 

 and again, in rolled pieces at the mouth of the Main river, near 

 Shane's Castle. 



It may be necessary to give some account of those fossil woods, 

 and to ascertain the class of vegetables to which they belong. It has 

 been already stated that they are found in two varieties of position ; in 

 the first they are associated with the lignites, under beds of clay ; in 

 the second they appear nearer the surface, in accumulation of trans- 

 ported matter. In the first position they are of a dark colour, and 

 scarcely distinguishable by the eye from the ordinary lignite. When 

 more minutely examined, they are found in some cases to consist of a 

 uniform mixture of carbonaceous and silicious matter; and when in 

 this state are very apt to be neglected, as it is ditficult to detect their 

 woody texture ; in other cases, even the layers of growth can be easily 

 observed. Yery frequently layers of woody matter still exist amid the 

 silicious substance, and, in that case, the two can be easily separated. 

 All the specimens split readily, in the direction of the fibres of the 

 wood. They are frequently covered on the surface with minute but 

 distinct crystals of quartz, which also penetrate their fissures. More 

 rarely, a thin coating of chalcedony has been observed. From these 

 circumstances it appears improbable that they could ever have been 

 transported ; for exposure to the weather whitens them, by removing 

 the carbonaceous matter ; and, as they are usually angular, and have 

 portions of wood adhering to them, or are studded over with crystals, 

 they cannot have been exposed to attrition. 



When found in the superficial alluvium, if long exposed, they are 

 usually of a looser texture, from the loss of woody matters. Their 

 colour, from the same circumstance, is white, and hence the notion 

 that they were specimens of petrified holly. Nothing is more common 

 than to find specimens which are black internally and white at the 

 surface ; and any black specimen may be whitened by burning. It is 

 in this state that most of the specimens are found, either when casually 

 turning up the soil, or in the courses of streams. 



The specimens vary in size ; sometimes weighing nearly a ton, as 

 in the splendid specimen preserved at Langford Lodge. They are also 

 very abundant in some places. I have seen a great number of fine 

 specimens in a garden in the village of Glenavy. 



