XO. lO SECOND REPORT ON FOLSOM COMPLEX ROBERTS 3 



to the eroding away of the ridges which once bordered it along one 

 side, now constitutes a terrace above an intermittent tributary to a 

 series of streams which ultimately join the South Platte River. The 

 work in 1934 was mainly confined to a deep deposit of midden material 

 exposed in the side of a ravine that cuts across the terrace in the zone 

 of former occupation, but traces of the cultural stratum were also 

 noted at several points along the edge of the terrace. The plan of pro- 

 cedure in 1935 called for the digging of two large trenches between 

 the edge of the terrace and the bank of the ravine (pi. i, fig. i). The 

 trenches were started several hundred feet apart at places where bones 

 and stone chips had been found the previous autumn but were directed 

 so that they would converge at the pit where most of the specimens 

 were obtained. This method of digging was adopted for the purpose 

 of exposing a complete cross-section of the fill overlying the old 

 \alley bottom and of determining, if possible, where the artifacts 

 found in the deep deposit had originated. 



The expedition did some work near the location of the original 

 Coffin finds. The preliminary report on investigations at the site dis- 

 cussed its discovery by Judge C. C. Coffin and his son A. L. Cofifin, 

 and the subsequent reporting of its existence to the Smithsonian In- 

 stitution by Maj. Roy G. Coffin, professor of geology at Colorado 

 State College.' The paper also pointed out that the material described 

 in it came from a place a quarter of a mile to the west of that where 

 the first Cofifin finds were made. In discussing the latter the writer 

 mentioned the fact that most of the Cofifin artifacts had been picked 

 up from the surface, which is the top of a hard, compact, tufaceous 

 layer, an Oligocene deposit, which underlies the entire site. The arti- 

 facts had undoubtedly been in top-level material that had been eroded 

 away by wind and water. Because of their weight the implements 

 remained until picked up. Portions of the sand, gravel, and nodule 

 layer which had overlain the compact deposit remained in some places, 

 and the Coffins had found a few objects on the contact line between 

 the two. After an inspection of the location the writer was dubious 

 about the possibilities of getting more information than that already 

 obtained by Judge and Major Cofifin but had discussed a tentative plan 

 of procedure with A. L. Cofifin. When the deeply buried deposit was 

 discovered in the ravine l)ank, indications were that it was a more 

 likely place for obtaining specimens from undisturbed layers, and 

 activities were concentrated at that point. 



During the winter and early spring following the writer's first ex- 

 cavations, the Coffins visited the site a number of times, and in 



"Roberts, 1935, pp. 1-3. 



