126 



THE POPULAR SCIENCE MONTHLY. 



a simple catalogue of them would occupy 

 several pages of this magazine. In so far 

 as the preservation of vegetables and of cer- 

 tain fruits is concerned a very fair measure 

 of success lias undoubtedly been achieved ; 

 but with flesh-meat the case is different. 

 We propose to describe here a few of the 

 chief methods adopted for preserving meats, 

 following for the most part a writer upon 

 this subject in the Journal of the Society of 

 Arts. These methods may all be reduced 

 under the four heads of Desiccation, Re- 

 frigeration, Use of Chemical Antiseptics, 

 and Application of Heat. Desiccation or 

 drying has been practised from the earliest 

 times. Charqui, or jerked beef, is an ex- 

 ample of fairly successful preservation, but 

 it is immensely inferior to fresh meat. Some 

 years ago the food committee of the Lon- 

 don Society of Arts reported favorably 

 upon some specimens of "powdered beef" 

 from Queensland; but the article has been 

 unable to win its way to public favor. The 

 reason of this no doubt is, that animal mat- 

 ter preserved by desiccation loses its flavor 

 and becomes tough and indigestible, the 

 fat becomes rancid, and in damp weather 

 the whole turns mouldy and sour. These 

 difficulties are to some extent obviated by 

 mixing absorbent substances with fatty 

 food, as in "pemmican," where sugar and 

 spice are mixed with dry powdered meat. 

 Meat-biscuit is made on a similar principle. 

 Tellier, of Paris, adopts the following meth- 

 od: He first exhausts the air from a close 

 vessel containing the meat, then fills it with 

 carbonic-acid gas, again exhausts and again 

 fills with the same gas. In this way the air 

 is almost entirely removed. He then ab- 

 sorbs the carbonic acid by the use of a con- 

 centrated solution of potash, by which a 

 very near approach to a vacuum is produced. 

 The meat is removed from the vessel after 

 three days, and may be kept sound without 

 further trouble, but it will have lost 20 per 

 cent, of its weight. 



The keeping of meat by refrigeration is 

 practised on a small scale in every house- 

 hold. The same thing was done on a large 

 scale at Melbourne in 1872, when a large 

 quantity of meat was kept for six weeks 

 perfectly fresh in an ice-chamber. In the 

 following year an attempt was made to ship 

 from Australia to England meat kept fresh 

 by the same method, but the experiment 



failed. Better success has attended later 

 shipments of meat from Canada to London, 

 and from Texas to New Orleans. The prog- 

 ress made in ice-making machines is such 

 as to inspire great hopes of success in pre- 

 serving meat by cold. 



Among chemical antiseptics common salt 

 of course holds a place. Many patents have 

 been taken out for the employment of 

 sulphur-fumes (sulphurous acid). Bisul- 

 phite of lime is very efficacious for the tem- 

 porary preservation of meat, and has been 

 practically tested with favorable results. 

 Our readers need not be reminded of what 

 is claimed for salicylic acid. Among other 

 chemical agents employed for this purpose 

 we may mention acetate of potash and chlo- 

 ralum. 



The expulsion of atmospheric air from 

 vessels containing meat, by means of heat, 

 is certainly the most successful method of 

 preservation yet adopted. Many difficult 

 processes are in use, but the main principle 

 expulsion of air by heat is the same in 

 all. They all, too, agree in this, that they 

 render the meat comparatively insipid. 



NOTES. 



The subject of iterated nesting by birds 

 being under discussion in Forest and Stream, 

 Dr. Charles C. Abbott contributes to that 

 journal the following list of birds which he 

 has himself observed nesting twice in sum- 

 mer : 1. Usually breeding twice robin, cat- 

 bird, bluebird, house-wren, yellow warbler, 

 English sparrow, bay-winged bunting, chip- 

 ping-sparrow, song-sparrow, orchard ori- 

 ole ; 2. Occasionally breeding twice white- 

 breasted nuthatch, scarlet tanager, yellow- 

 bird, chewink, Baltimore oriole, purple gra- 

 kle. 



The American Metrological Society has, 

 through its president, memorialized Con- 

 gress for the preparation of coins, of metri- 

 cal weight and uniform fineness, and for the 

 passage of laws and conclusion of treaties 

 whereby such coins shall become legal ten- 

 der, according to their weight. 



A crucial experiment was recently 

 made at Sunderland, England, on a fire- 

 proof house. One of the rooms was filled 

 with tar-barrels, wood, and other combusti- 

 ble material, and, when the door was shut, 

 the mass was set on fire. It simply burnt 

 itself out, without apparently affecting the 

 condition of the adjoining rooms or the sta- 

 bility of the house itself. The building ma- 

 terial was a concrete of cement and fibre 



