HAWORTH AND BENNETT.| History of Field Work. 47 
pointed out here, not with a spirit of criticism, but because it 
should be known in order to set ourselves right for the system 
of nomenclature adopted later in this volume. For example, 
on page 47, Swallow speaks of the “Well Rock” as outcropping 
on Sugar creek in Anderson county, where it is forty-eight 
feet thick. He then describes it as being in the ford of the 
Marais des Cygnes on the “Telegraph road,” where it is eight 
feet thick. ‘‘Thence it may be traced from stream to stream 
and slope to slope till found near high-water mark at Lecomp- 
ton and on the tops of the ridges at Lawrence. This last posi- 
tion it holds in the ridge to Leavenworth, where it is bluish- 
gray and brown and subcrystalline. Thence it continues cut- 
ting ridge and valley to Wolfe river and to the northern border 
of the state.” 
By turning to his system of classification, page 20, it is 
found that he places the Well Rock series first below the 
Spring Rock series, that below the Cave Rock series, and that 
in turn below the Stanton limestone series, making an aggre- 
gate, according to his figures, of 237 feet below the top of the 
Stanton limestone series. 
We now know that he confounded the Oread limestone, 
which occurs at Lecompton, Lawrence, Leavenworth, etc., with 
this Well Rock series. The Oread is fully 300 feet above the 
Stanton rock of Swallow along the Marais des Cygnes, which, 
~ added to the 237 feet just mentioned, makes an error of fully 
537 feet in this connection. 
On page 20 his number 156 is called Cave limestone, and is 
given as occurring at Beaver, Sugar creek, and at Topeka. 
The limestone at Topeka here referred to is fully 700 feet 
above the limestone he refers to along Sugar creek, and to go 
from one to the other one must cross over not only the Oread 
limestone, the Lawrence shales and the Stanton limestone, but 
all of the limestones and shales lying between the Oread and 
the Topeka limestones. On page 21 Swallow mentions the 
Spring Rock series, which he numbers from 158 to 168, in- 
clusive. Number 162 of this series he labels Spring Rock and 
gives for its locality Beaver creek, Marais des Cygnes, John- 
son’s coal-bed west of Topeka, and Lecompton. Here again 
he covers a vertical distance of fully 700 feet, and crosses 
about as many different formations as he does with the Cave 
Rock series. He has thus intertwined the various strata of 
his Cave Rock, Spring Rock, and Well Rock series much as 
