THE FARMERS' REGISTER. 



173 



heard from William Weeks, an intelligent observ- 

 er, and now the oldest man living in that neigh- 

 borhood. 



Mr. Selden's oxen now (raised on the farm) 

 are much finer animals than are often met with in 

 eastern Virginia. He sold two pairs not long 

 since to be worked at (he Navy Yard, Poris- 

 mouth, for $100 ihe pair, which ie about double 

 the usual price of what are called very good oxen. 

 Those we saw at work would prove that his cat- 

 tle fare well, and likewise that the cause ofthe dis- 

 temper is not (as some suppose) to be Ibuiid in 

 clover, or other good grass, being plentiful, and 

 the cattle being lat. 



The Hessian fly, so destructive to wheat else- 

 where and generally, is not Ibund to be any im- 

 portant cause of diminution to the crops at West- 

 over. If sown in good time, (say commencing 

 the 10th ol October,) and the land is good and 

 well prepared, the vigor of the grovvih will be 

 sufficient protection against the attacks ol the 

 fly. Mr. Selden does not doubt but that these 

 insects are numerous in his wheat, and does not 

 suppose that their depredations are harmless. 

 But at least they show such little effect, as never 

 alone to have prevented the making a good crop 

 from good land, other circumstances being not 

 unfavorable. 



In my own practice, I have found no such ex- 

 emption from this infliction. But my land was 

 not only much less fit to bear heavy crops of wheat, 

 and my cultivation far less perfect than here, but 

 also, the wheat fields were not grazed and glean- 

 ed after harvest by slock, and therefore all the 

 wasted grains grew to furnish food for an inter- 

 mediate brood of Hessian fly. And if there are 

 successive broods of the fly, this must be a very 

 efficient means to nourish and increase them. I 

 am now convinced of my error in adhering so en- 

 tirely and so long to the non-grazing system. 

 Besides the benefits that I would count on to the 

 Block from gleaning the wheat fields after harvest, 

 and the preventing the growth of volunteer wheat 

 to sustain a new brood of Hessian fly, Mr. Sel- 

 den thinks that the partial grazing of ihe field, 

 or rather the trampling which accompanies it, is 

 essential to the best success of the clover sown 

 on the wheat. And if the grazing after harvest 

 is beneficial, for this reason, on the stiff' loam ol 

 Westover, it must be much more necessary and 

 desirable on soil too light to be well adapted to 

 wheat. 



OIL AND STEARINE FROM LARD, &C. 



Published by the National Agricultural Society. 



[The following communication on the subject 

 of oil and slearine, has, on request, been trans- 

 mitted to the Commissioner of Patents, and will be 

 read with interest.] 



Stearic acid, or stearine, as it is improperly 

 called, is the solid constituent of fatty substances, 

 such as oil, tallow, lard, &c., and which can be 

 separated in a crystalline form by saponification 

 with alkaline matter and abstraction of the alkali 

 by an acid. By this process fats are convertible 

 into the stearic, margaric, and oleic acids combin- 

 ed, to separate which alcohol is used, which holds 

 the two latter in solution alter having dropped the 

 Btearie acid in crystals. 



Pure stearic acid is prepared thus : boil together 

 in the proper equivalent proporiions a solution of 

 an alkali, say potash with tallow ; by this process 

 a soap is formed ; ol this soap dissolve one part 

 in six parts of hot water, then add to the solution 

 40 or 60 pans of cold water, and set ihe whole 

 where the temperature is about 52° Fahrenheit. 

 The bistearaie and bi-margnraie of potash, pearly 

 in appearance, fall to the bottom, which are to be 

 separated by and washed upon a filter. An ad- 

 ditional quantity of these salts is afforded by eva- 

 porating the filtered liquor, saturating with an 

 acid the alkali left free by the precipitation of the 

 above sails, and then adding water. By a re- 

 petition of this operation, il conducted carefully, 

 the solution ia freed from all of these solid acids, 

 leaving ihere'bre noihing but ihe oleic. After 

 having washed these bi-salte, digest them in 

 twenty-four times their weight of boiling alcohol 

 of specific gravity 0.820, upon cooling the bi- 

 siearate precipiiatep, while the greater part of the 

 bi-margarate and the remainder of the oleale is 

 held in solution. By rediesolving in alcohol as 

 before, the whole ofthe bi-margarate is got rid of, 

 leaving the bi-stearaie alone, the purity of which 

 can be tested by decomposing a small portion in 

 water at the boiling lemperaiure with hydrochloric 

 acid, letting it cool, washing the stearic acid ob- 

 tained, and exposing it to a heat, which, il pure, 

 will not melt in water under 158° Fahrenheit; 

 should it fuse at a lower temperature, it is to be 

 inferred that there is more or less margaric acid 

 present, to get rid of which repeat the solution in 

 alcohol in the mode as directed before. 



We then have pure bi-stearate potash. From 

 this we separate the stearic acid, by decomposing 

 it in boiling water with hydrochloric acid. The 

 stearic acid which falls down, is to be washed by 

 melting in waler, cooled, dried and dissolved in 

 boiling alcohol, firom which crystals will fail dur- 

 ing refrigeration. 



Thus obtained, the stearine contains combined 

 water, from which it is difficult to separate it. 



In June, 1825, a patent was granted in Eng- 

 land to Mr. Gay Lussac for making these candles, 

 but owing to their comparatively great cost, they 

 could no*, although superior to other kinds, be in- 

 troduced into general use. Lately, however, the 

 great objection has been obviated by the many 

 improvements which have been made in the 

 modus operandi of manufacturing these candles. 

 The subs'itution of lime for potash in saponifying, 

 is one of the most important ; and to such per- 

 fection has the process now been brought, that 

 the London block, containing only 3 per cent, of 

 wax, and from which these candles are made, 

 bears so handsome an appearance, and is of so 

 good a quality, as to render it difficult to distin- 

 guish it fi-om the most refined product of the bee. 



The followine is the process by which these 

 candles are made on a large scale, both in Eng- 

 land and France : 



Tallow, lard, or any fat, is boiled with quick- 

 lime and water in a large vat, by means of per- 

 forated steam pipes distributed over its bottom. 

 After several hours' active boiling, the combina- 

 tion becomes sufficiently complete. The stearate 

 thus formed is allowed to cool until it becomes 

 a concrete mass ; it is then to be dug out, trans- 

 ferred to a suitable vessel, and decomposed by a 

 sufficient quantity of sulphuric acid. This de- 



