164 APPENDIX (PART II) 



The nature photographer will find that when he wishes to take pictures of small 

 insects as large or larger than life, that an ordinary camera will not extend 

 sufficiently to give the required size. In the camera under consideration, 

 the front focusses as well as the back, and so an extra extension up to 21 

 inches is obtained. It is often exceedingly useful to have a camera which 

 focusses at the back, for instance when it is necessary to take a picture 

 through a small hole or through the bars of a cage. Messrs W. Watson 

 & Sons, of 313 High Holborn, have kindly undertaken to make this 

 camera, which without lenses or shutter costs .15, including a tripod 

 and three double slides. A holostigmatic lens is <7, 5s., and an " Everset " 

 shutter 2, 15s. See page 50. 



For photographing clouds process plates are recommended. 



Ordnance Survey Maps are now supplied to schools for the bona fide use of 

 scholars at a very cheap rate on application to the Director-General, 

 Ordnance Survey, Southampton. Two hundred copies (no less number 

 will be printed) of a map up to 18"xl2", from one sheet cost (a) for 

 "outline," 25s. ; (b) for "hill-shaded," 35s. See page 51. 



Gum tragacanth mixed first of all with spirit, and then brought to the right con- 

 sistency with water, is useful for attaching small things (which are to be 

 kept in spirit) to sheets of glass. For large specimens, a mixture of glue 

 and turpentine such as is used for sealing the lids of museum jars contain- 

 ing spirit should be adopted. It is made as follows : 



The best Scotch glue is broken up into small knobs and allowed to lie over 

 night in a flat dish of water which should cover half its depth. In the 

 morning it is placed in a tin and heated over water. N.B. If the tin is 

 placed in a saucepan, nails or something else should be placed in the latter, 

 so as to allow water to run beneath the tin. When the process is com- 

 pleted, turpentine should be poured on to the surface in the proportion of 

 about an ounce or an ounce and a half to every four ounces of glue 

 originally taken. The material is used hot. 



Boxwood topped bottles with wide mouths (" Pomades"), one ounce size, can be 



