GENERAL REMARKS. 89 



ingredients as wanted. The great objection to this and to all 

 the "coagulines" is that the edges of the specimen require 

 warming, which cannot always be done. 

 Another good colourless cement is — 



No. 3S.— White Cement, No. 2. 



Gum tragacanth in powder, 1 part. | Gum arabic (acacia) in powder,! part. 

 Glacial acetic acid, a few drops. 



"When used, moisten the gums with a little of the acetic acid 

 diluted. 



Gum mastic dissolved in alcohol, and white shellac dissolved 

 in naphtha, are two other white cements. 



Where, however, colour does not matter, take — 



No. 34. — Brown Cement. 

 Common shellac, ilb. | Spirits of naphtha, |- pint. 



Place them in a bottle in a warm situation on a closed stove, 

 or in a vessel containing hot water. Be careful of fire. The 

 edges of bones or undersides of fossils are smeared with this, 

 tied with string, and left for a day or so to unite. 



The reader has now a repertoire of poisonous and harmless 

 preparations from which he may choose. As for myself, for the 

 preservation of birds, I pin my faith to formula No. 4, viz., 

 my Preservative Soap for the inside of the skin, and a wash of 

 benzoline or turpentine liberally applied from time to time — say 

 twice a year — to the outside of all uncased or exposed specimens. 

 This, it will be seen, entirely does away with the use of any 

 poison, and yet is proved to be of the highest efficacy. 



Por those who do not object to expense nor to the use of a 

 poisonous preparation, a wash of Waterton's Solution (No. 5), 

 or the sulphuric ether preparation (No. 18), can be substituted 

 for benzoline or turpentine. I mention the expense, because 

 only rectified spirits of wine, or pure sulphuric ether, will do for 

 birds ; the methylated spirit, though of service for washing 

 over most subjects, is not so good when applied to the delicate 

 feathers of birds, as it leaves on drying a certain impure 

 residuum behind it. 



Por mammals I recommend my formula of burnt alum and 

 saltpetre (No. 9), followed by a wash of benzoline or turpen- 



