saul PREFACE. 
a study of their fossil contents. Correct inferences as to their 
economic value and the ready and accurate determination of their 
occurrence depend largely upon a precise knowledge of these points. 
A striking example of this indirect economic value of paleonto- 
logical studies was seen in connection with these very mmvestiga- 
tions. Very early in the work it was found that the earthy lme- 
stone, so extensively used in the vicinity of Phillipsburg for the 
manufacture of Portland cement, as well as the pure non-magnesian 
limestone used with the cement rock to increase the percentage ot 
lime, belonged to the Trenton formation, and was readily recog- 
nized by the fossils it contained. It was found to oceupy a definite’ 
position in respect to the underlying Kittatinny limestone, which 
was highly magnesian and of no value for Portland cement, and 
the overlying Hudson River slate. This fact being determined, it 
was a comparatively rapid and easy matter to trace the boundaries 
of the formation and so determine the location of these beds. It 
was at once possible to eliminate a large area from the field of 
investigation, with great saving both of time and money. In fact, 
the Report upon the Portland Cement Rocks* could not have been 
prepared, without the expenditure of a much greater sum than 
was involved, if it had been necessary to examine the whole area 
of Paleozoic rocks with as much detail as was given to a few com- 
paratively narrow zones. 
But even if the study of these faunas were totally unproductive 
of any economic results, direct or indirect, nevertheless, their in- 
vestigation is a legitimate part of the Survey work. It is worthy 
‘science for seience’s 
‘ 
the honor and name of the State to foster 
sake,” and to carry on investigations which add something to the 
sum of human knowledge. When it is remembered that these 
fossils are the remains of living forms—some of them the highest 
forms of life of their time—and that from these lowly forms has 
come, through countless years, the grand culmination of the lite 
of to-day, a new interest. is aroused. They cease to be mere bits 
of stone, curious but meaningless, and become instead the touch- 
stones to the past. 
, HENRY PB. KUMMEL. 
*Ann. Rep. for 1900. 
