13 



never hitherto been attempted in a complicated district. But it 

 was mapping executed by a man who was the keenest of observers, 

 and who had by this time made himself perhaps the greatest master 

 of the craft in the whole world. 



Lapworth possessed a very sharp eye for lithological variation, 

 and a vivid memory for lithological type. These he used in tracking 

 the beds from point to point. At the same time he collected the 

 graptolites from each bed as an additional means of recognising 

 it, and as he acquired skill in their identification each group of 

 graptolites became the ' hall-mark ' of. its own bed. It was only 

 when 'this dual means of recognition had unravelled the structure 

 that the relations and sequence of the strata were revealed. 



Thus the Southern Upland work was for the most part self- 

 contained. Although, as has been already and will be again 

 pointed out, Lapworth was at this time aware of all that had been 

 done by others on the rocks and fossils of the Lower Palaeozoic 

 Group, and had himself begun to carry out work of comparison 

 in many districts where knowledge was incomplete or inexact, 

 this knowledge was not allowed to influence him in working out 

 the detail of his own district, in forming any theories as to its 

 structure, or in presenting his case to his compeers of the Geological 

 Society. 



The graptolites were used as symbols to help in unravelling 

 the structure the structure as it became known revealed the 

 succession of the beds, and this, in its turn, disclosed the succession 

 and relation of the faunas. 



How welcome these results must have been to Lapworth 

 we realise from his own words that *" zonal work is probably 

 destined to effect in the history of geological research a revolution 

 as great and an advance as rapid as those brought about by the 

 use of the microscope in the history of biology." 



It might have been expected that among scientific men such 

 a vindication of scientific law would have received the warmest 

 of welcomes. This, however, was not the case, for Barrande, 

 whose theory of ' colonies ' had received its deathblow, declined to 

 acknowledge defeat, and even named a newly discovered ' colony ' 

 after Lapworth. Also in a work published a few years later we find 

 the following footnote appended to a statement of the old views 

 as to the Upland sequence : 



" Mr. Charles Lapworth, who has devoted much time to the 

 study of the graptolites of these rocks, has come to the 

 conclusion that what is here termed the Moffat shale group, 

 and regarded as merely a subordinate member of a thick 

 series of sandy and generally unfossiliferous strata, represents 

 the whole series of strata from the Llandeilo up into the 



* 56, p. 520. 



