Domestic Economy. 4.77 



black, is very inferior; for, although when mixed up it soon hardens on the 

 surface, underneath it remains soft, and easily crumbles between the thumb 

 and finger : another proof of its inferiority, and which is of main impor- 

 tance to the surveyor and builder, is the small proportion of sand which it 

 will bear, while, on the other hand, genuine cement is better when used 

 with an equal quantity of sand ; it adheres stronger, dries of a light brown 

 colour, and hardens all through." {Times, December 1. 1826.) 



Art. VIII. Domestic Economy. 



Method of preparing the Pectic Acid, communicated by Professor Dr. A. T. 

 Thomson. — Take any quantity of carrots ; wash and clean them well • then 

 by means of a rasp, reduce them to a pulp ; express this strongly, and wash the 

 marc with distilled or filtered rain water until it cease, by expression, to be coloured. 

 Mix fifty parts of the washed marc, expressed, with three hundred parts of dis- 

 tilled water, and one part of a solution of caustic potash ; then heat the mixture 

 till it boil, and let it boil for a quarter of an hour, or until a portion of the fluid 

 coagulate completely into a jelly with an acid. Pass, now, the boiling liquor 

 through a cloth, and wash the mass with distilled or Jittered rain water, mixing these 

 washings passed through the cloth with that which was strained while hot. The 

 mixed fluid should become thick and gelatinous on cooling. This contains a 

 pectate of potass, which may be decomposed by a small quantity of muriate of 

 lime, largely diluted with distilled water, by which means an insoluble gelatinised 

 pectate of lime is formed, which should be well washed on a cloth. The washed 

 pectate is next to be boiled, for a few minutes, with distilled water, acidulated with 

 muriatic acid, to dissolve the lime and the starch ; and, by then throwing the 

 whole on a cloth, and washing it with distilled water, the pectic acid is procured. 



The pectic acid, thus obtained, liquefies readily on admixture with a few drops 

 of solution of ammonia ; and, by evaporating this fluid in porcelain dishes a 

 super-pectate of ammonia is procured, which swells very much in distilled water • 

 and, as it dissolves, thickens a large portion of that liquid. 



Either the pectate of ammonia or the gelatinised acid may be employed for 

 forming jellies. If the latter be used, the following process must be followed. 

 Take one part of the gelatinised acid, well drained, and three parts of distilled 

 water ; add to this solution a small quantity of solution of pure potass, largely 

 diluted, until the acid be saturated, which must be determined by litmus paper. 

 Heat this mixture, and add to it three parts of sugar, which have been rubbed on 

 lemon peel ; next decompose the pectate by very dilute muriatic or sulphuric 

 acid, and agitate the fluid, which in a few minutes afterwards will form a jelly. 

 The jelly thus formed may be flavoured with vanilla, orange flowers, cinnamon, 

 or the rose, at pleasure ; or a very useful gelatinous lemonade may be made, by 

 addition of lemon juice. If these jellies do not contain a sufficient quantity of 

 sugar, they become mouldy, but never ferment. 



M. H. Bracconot asserts, that these jellies are certain antidotes against the 

 poison of the salts of lead, copper, zinc, antimony, and mercury ; with the excep- 

 tion of corrosive sublimate and emetic tartar. They neutralise and involve the 

 deleterious salts, and allay the irritation of the intestines, which may have been 

 induced. {Annals de Chimie et de Physique, torn. xxx. p. 102. 968.) 



Extracting Wax from Bee Combs. — Have on the fire an open vessel of boiling 

 water, and standing by the fire an open vessel of cold water ; put the comb, close 

 tied in a canvass bag, into boiling water, and repeatedly squeeze it down with a 

 stick or large wooden spoon. The wax will come through the bag, and swim on 

 the surface of the water ; skim it off, and put it in the vessel of cold water. By 

 repeatedly squeezing the bag and skimming, every particle of wax will be ob- 

 tained. When congealed on the cold water, it may be taken off, again melted, 



