REPORT OF COMMITTEE ON PHOTOGRAPHS. 617 



Each photograph should be plainly labeled, giving the subject, with a brief but 

 explicit reference to what is illustrated by the photograph, its date, locality, and the 

 name of the artist and donor, and a reference to its publication, if the photograph 

 has been published, either in type or plate. The label should be placed, if in type, 

 upon the front, beneath the photograph ; if in script, upon the back. 



The photographs should be accompanied by a statement whether duplicates and 

 lantern slides can be furnished, and at what price, and the address of the person to 

 whom application for them should be made. It is suggested that in order to save 

 trouble to the donors, arrangements be made with local photographers, to whom 

 the negatives may be intrusted, to fill orders. 



Kegister of Photographs Keceived in 1890. 



The following is a complete register of the photographs collected previous to the 

 Washington meeting. It contains the running numbers of the photographs by which 

 they can be ordered, their labels, sizes, dates, the cost of duplicates, as well as the 

 names of the photographers and the donors ; also directions as to where duplicates 

 and lantern slides may be obtained. 



Professor J. F. Kemp presented 21 photographs, numbered from 1 to 21 inclusive. 

 All but 18-21 were photographed by Mr. Kemp. Their size is 5 by 7 inches. They 

 may be ordered of him at |0. 10 unmounted, $0.12 mounted, postage extra. 



1. Boss or knob of so-called porphyrite, associated with the elaeolite-syenite near 



Beemerville, New Jerse3\ (Am, Jour. Sci., 8d ser., vol. XXXVIII, p. 130.) 

 June, 1888. 



2. The Sopris coal mines, near Trinidad, Colorado. The mines enter the hill just 



in the rear of the engine-house. September, 1888. 



3. Coal mines and butte at Rouse, near Walsenburg, Colorado. Characteristic 



scenery of the eastern foothills. September, 1888. 



4. View of Mount Sopris, western Colorado, from the Spring Gulch coal mines 



across Jerome park. The point of view is on the Laramie. The intervening 

 upturned strata are Mesozoic and Paleozoic. August, 1888. 



5. The Sunshine coal mines, Jerome park, northwestern Colorado. The Laramie 



sandstones show in section on the right, dipping westward. September, 1888. 



6. Open cut and stopes at Pilot Knob, Missouri, showing the relations of the specu- 



lar hematite to the porphyry, and also the thickness of the ore body. Septem- 

 ber, 1888. 



7. Open cut at Pilot Knob, Missouri, showing the specular hematite interbedded in 



porphyry and slate. September, 1888. 



8. Open cut at Iron Mountain, Missouri. Photograph taken on a very cloudy day. 



September, 1888. 



9. Red Cambrian quartzite, as exposed in the quarries at Willard's ledge, Burling- 



ton, Vermont. Dip 10°-15° E. July, 1839. 



10. Trap dike in red Cambrian quartzites at the Willard's ledge quarries, Burlington, 



Vermont. July, 1889. 



11. Red Cambrian quartzite at the Red Rocks, just south of Burlington, Vermont. 



Dip 15°-20° E. The water is Lake Champlain. July, 1889. 



12. Overthrow of Cambrian sandstone on Utica slate. Lone Rock point, just north of 



Burlington, Vermont. The water is Luke Champlain. July, 1889, 



