66 



To the total quantity of the dry food as above add about one-and-a- 

 half times as much fat, beef or mutton suet. As the fat easily 

 evaporates in a fluid condition, more suet must be added after the 

 mixture has been warmed several times. Food made from this recipe 

 is sold by the firm of Hermann Scheid, at Biiren, in Westphalia, under 

 the name of " Food-stones." 



It is by no means necessary to keep closely to the recipe ; it is only 

 to serve as a guide, and can be altered. The chief part of the mixture 

 must, however, always consist of hemp, whole or crushed. 



This mixture is heated on the fire if prepared at home the fat must 

 be melted and then the dry foodstuff put in well stirred, and, when 



FIG. 1. HEATING APPABATUS (CLOSED). 



boiling, poured on the branches of the tree. It is essential that the 

 liquid mass should penetrate through the leaves to the branch itself, 

 and this can only be done when it is very hot. It is a mistake to spread 

 the mass on the branches when it is beginning to cool, for this brings 

 about the very thing we want to avoid a greater surface of food is 

 exposed ; it is covered by ice, hoar frost, and snow, and is rendered 

 naccessible to the birds. 



At the Seebach experimental station, and in many other places, a 

 special warming apparatus is used to prepare the " food- tree." Not 

 only are the separate parts very useful for pouring on the food, but it 

 has this very great advantage, that the hot food can be kept warm for 

 a long time. 



Fig. 1 shows the apparatus closed, while Fig. 2 shows clearly its 

 constituent parts two receptacles, one on the top of the other, of the 



