RECORDS 115 



stones. The various sands referred to in these remarks were 

 illustrated by photomicrographs. 



A Method of Facilitating PJiotograpJiy of Fossils was described 

 by Mr. Gilbert van Ingen. The speaker noted the difficulties 

 met by all investigators in the illustration of their specimens. 

 All methods by which the published figure is derived from an 

 original drawing produced by hand-work are dependent for their 

 degree of correctness upon the accuracy of eye and skill of hand 

 of the draughtsman. Such figures contain a variable percent- 

 age of the personal element which the artist unconsciously in- 

 corporates into his work. The majority of investigators find it 

 difficult to. produce a drawing of satisfactory excellence and at 

 the same time have not at their disposal the means wherewith 

 to engage the services of a trained artist. Photography, often 

 employed as affording a correct and cheap method of illustra- 

 tion, has, up to the present time, yielded results of varj'ing and 

 uncertain degrees of accuracy. The difficulty of obtaining a 

 satisfactory negative from the object has caused direct photog- 

 raphy to be looked upon by disfavor by many palaeontologists. 

 This difficulty is due to the effect upon the photo-plate of the 

 colors and reflected light emanating from the surface of the 

 specimen to be photographed. A method of illuminating these 

 disturbing elements was sought and, at the suggestion of Pro- 

 fessor Kemp, the use of ammonium chloride was tried. 



A simple apparatus has been devised by which a fossil of any 

 size can be coated with a thin, opaque, white film which effec- 

 tually illuminates under the influence of both color and reflected 

 light. The necessar}' articles for construction of the apparatus 

 are : a foot-blower, large wide-mouthed bottle of gallon capacity, 

 with three-holed rubber stopper, two bottles of quart capacity, 

 each with two-holed rubber stopper, glass tubing of one-eighth- 

 inch bore and rubber tubing to fit same (three feet of each), two 

 U-shaped calcium chloride tubes filled with chloride, strong 

 ammonia water, strong HCl. To use : Air from the foot- 

 blower is forced into the large bottle, which equalizes the pres- 

 sure, and thence through the ammonia water and HCl into the 

 smaller bottles. The air, mixed with the gases taken up, is 



