THE WOMBAT. 93 



properties of the cement. When cement begins to set 

 crystals are formed, which, when united, become one solidified 

 mass, and when the setting action once commences the less 

 the mass is disturbed the better. Another evil is in not 

 having the walls thoroughly wetted when plastering. The 

 water that is added to cement is put there for a purpose — to 

 make it set ; now if you put this mortar on to a dry wall the 

 bricks readily absorb a great deal of the water, and deprive 

 the cement of what it requires in order to set and harden. 



In the summer months, in a hot climate like ours, 

 plastering, and even brickwork in cement, should be well 

 hosed down with water every day for a week or so after the 

 work is done, and on a north wind day no outside plastering 

 should on any account be allowed. 



PHOTOGRAPHIC SURVEYS.* 



By C. H. B. 



Now that the value of photographic records of various 

 objects of historical and archaeological interest has received 

 definite and official recognition from the authorities of the 

 British Museum, it is probable that an active interest in 

 photographic surveying will become more general amongst 

 photographers throughout the country instead of being con- 

 fined, as heretofore, to a few of the more active societies. 

 One of the chief difficulties, we believe, that has stood in the 

 way of the general prosecution of such work, has been that of 

 securing a satisfactory custodian of the results, but now that 

 the British Museum has, very properly, undertaken the duty, 

 this difficulty is removed. We feel sure that everyone with 

 historical or antiquarian interests will agree that in taking up 

 this work — and it will be anything but light work before it is 

 completed — the museum authorities are doing that which 

 could not with equal appropriateness be undertaken by any- 

 one else. At the same time it seems to us that it would be 

 regrettable if the results of photographic surveys should be 

 accessible in one place only, even though that place be London. 

 Apart from general interest in historic or prehistoric remains, 

 wherever they occur, most people feel, naturally enough, a 

 keener interest in such remains as occur in their own particular 

 locality. We see evidence of this in the numerous local 

 archaeological societies. It would seem, therefore, that, in 



* Photography. 



