May 11, 1883.] 



KNOWLEDGE ♦ 



275 



course, the higher the initial outside temperature, the more 

 rapidly the heat will penetrate ; but we cannot apply this 

 law to a lump of meat as we may to a mass of iron. We 

 may go on heating the outside of the iron to redness, but not 

 so the meat So long as the surface of the meat remains 

 moist, we cannot raise it to a higlier temperature than the 

 boiling point of the liquid that moistens it. Above this, 

 charring commences. A little of such charring, such as 

 occurs to the steak or small joint during the short period 

 of its exposure to the great heat, does no harm ; it simply 

 "browns " the surface ; but if this were continued during 

 the roasting of a large joint, a crust of positively black 

 charcoal would bo formed, with ruinous waste and general 

 detriment. 



As Rumford proved long ago, liquids are very bad con- 

 ductors, and when their circulation is prevented by confine- 

 ment between fibres, as in the meat, the rate at which heat 

 will travel through the humid mass is very slow indeed. 

 As few of my readers are likely to fully estimate the 

 magnitude of this ditliculty, I will state a fact that came 

 under my own observation, and at the time surprised me. 



About five and twenty years ago I was visiting a friend 

 at Warwick during the "mop," or "statute fair" — the 

 annual slave market of the county. In accordance with the 

 old custom, an ox was roa?tcd whole in the open public 

 market-place. The spitting of the carcass and starting the 

 cookery was a disgusting sight. We are accustomed to see 

 the neatly-cut joints ordinarily brought to the kitchen ; but 

 the handling and impaling of the whole body of a huge 

 beast by half-a dozen rough men, while its stiffened limbs 

 were stretching out from its trunk, presented the car- 

 nivorous character of our ordinary feeding very grossly 

 indeed. 



Nevertheless I watched the process, and dined on some 

 of its result. The tire was lighted before midnight, 

 the rotation of the beast on the horizontal spit before it 

 began shortly after, and continued until the following mid- 

 day, all this time being necessary for the raising of the 

 inner parts of the flesh to the cooking temperature of about 

 180° Fahr. 



Compare this with the grilling of a steak, which, when 

 well done, is done in a few minutes, or the roasting of the 

 small joint as above within thirty minutes, and you will 

 see that I am justified in dwelling on the great differences 

 of the two processes, and the necessity of very varied pro- 

 ceeding to meet these different conditions. 



The difference of time is so great that the smaller 

 relative surface is insufficient tj compensate for the evapo- 

 ration that must occur if the grilling principle, or the pure 

 and simple action of radiant heat, were only made available, 

 as in the above ideal roasting of the small joint. 



What, then, is added to this 1 How is the desiccating 

 difficulty overcome in the large-scale roasting 1 Simply 

 by baslin;/. 



All night long and all the next morning men were con- 

 tinuously at work pouring melted fat over the surface of 

 the slowly-rotating carcase of the Warwick ox, skilfully 

 directing a ladleful to any part that indicated undue 

 dryness. 



By this device the meat is more or less completely enve- 

 loped in a varnish of hot melted fat, which assisted in the 

 communication of heat, while it checked the evaporation of 

 the juices. In such roasting the heat is partially communi- 

 cated by convection through the medium of a fat-bath, as 

 in stewing it is all supplied by a water-bath. 



I purpose making an experiment, whereby this principle 

 will be fully carried out. I shall melt a sufficient quantity 

 of mutton fat to form a bath, in which a small joint of 

 mutton may be immersed, or of beef fat for beef ; and then 



keep the melted fat at about tlie cooking temperature, or a 

 little above it — say the boiling point of water, which will 

 be indicated by the spluttering due to the evaporation of 

 the water in the meat The result of this experiment will 

 be duly reported to the readers of KxowLEDt:E when I reach 

 the general subject of frying. In my next I must continue 

 this subject of roasting, which is by no means exhausted 

 yet. Count Rumford devotes seventy pages to it, and I quote 

 his words for my own use. He says,* " I shall, no doubt, 

 be criticised by many for dwelling so long on a subject 

 which to them will appear low, vulgar, and trifling ; but I 

 must not be deterred by fastidious criticisms from doing all 

 I can do to succeed in what I have undertaken. Were I 

 to treat my subject superficiall)', my writing would be of 

 no use to anybody, and my laVjour would be lost ; but by 

 investigating it thoroughly, I ina)', perhaps, engage others 

 to pay that attention to it which, from its importance, it 

 deserves." 



In my last, col. 1, page 247, is an error that must have 

 puzzled some readers: on line 16, for "dissected," read 

 " desiccated." 



The Boston (U.S.A.) Evening Transcript, in referring 

 to electric companies generally, says the best that can be 

 said in their favour is that they are now endeavouring to 

 do as little business as possible, for the more they do the 

 more they lose. [Of some companies this is quite true, but 

 certainly not of all. ] 



It is stated that one of the palace cars belonging to the 

 United States Fish Commission started recently for Cali- 

 fornia with a passenger list of young fish numbering 

 18,000. The middle part had an aisle running through the 

 centre, and in place of the seats on each side, were wooden 

 ledges, about 3 ft. high, on which were placed the tin fish- 

 tanks. The fish were not placed in the tanks filled with 

 water, as the motion of the train would dash the water 

 about and destroy many lives among the young passengers. 

 But, instead, about twenty fish were placed in gallon tin pails, 

 and these pails were put in the tanks, and then the latterfilled 

 with water. With the carp, however, the water in the 

 pails was sufficient, and the motion of the car tended to 

 the circulation of air in the water, keeping it fresh. The 

 attendants renewed the water every eight hours, and kept 

 a careful watch to remove any fish that might have died. 

 The percentage of fish lost by death, however, was very 

 small. 



The Raihoay Revieio (Chicago, March 21) quotes 

 from the Medical and Surgical Jourivxl some very 

 unfavourable comments upon a Bill lately introduced 

 into the United States Legislature, to put a stop to 

 the use of any test for the form and colour sense 

 of railway employes, except by the railway signals 

 themselves. This paper states that it has been re- 

 peatedly and clearly shown that not even the most 

 skilled experts can detect colour-blindness or decide 

 upon a man's eyesight by any use of the railway 

 signals. On the other hand, a very few minutes with the 

 most practical test used by the Government will settle 

 whether a man is safe or not. There is strong reason to 

 believe that the seemingly plausible argument of allowing 

 experts or others to test only by railway signals, arises 

 from the desire to break down the law which practically 

 prevents the colour-blind or purblind from holding positions 

 in which their defects endanger lives and property. 



* " Essaya Political, Economical, and Philosophical." Vol. III.. 

 page 129. 



