June 22, 1883.] 



♦ KNOWLEDGE ♦ 



371 



Although no mention is made by Runiford of such de- 

 struction of the blowpipes, he was evidently conscious of 

 the costliness of his original roaster, as he describes 

 another which may be economically substituted for it. This 

 has an air chamber formed by bringing the body of the 

 oven door so as to enclose the space occupied by the blow- 

 pipes shown in Fig. 1, and placing the dripping-pan on a 

 false bottom joined to the front face of the roaster just 

 below the door, but not extending quite to the back. An 

 adjustible register door opens at the front into this air 

 chamber, and when this is opened the air passes along 

 from front to back under the false bottom, and rises behind 

 to an outlet pipe like that shown at r Fig. 1. In thus 

 passing along the hot bottom of the oven the air is heated, 

 but not so greatly as by the blowpipes, which being sur- 

 rounded by the flame on all sides, are heated above as well 

 as below, and the air in passing through them is much 

 more exposed to heat than in passing through the air- 

 chamber. 



To increase the heat transmitted in the latter. Rum- 

 ford proposes that " a certain quantity of iron wire, 

 in loose coils, or of iron turnings, be put into the air 

 chamber." 



This modification he called a " roasting oven," to dis- 

 tinguish it from the first described, the " roaster." He 

 states that the roasting oven is not quite so effective as the 

 roaster, but from its greater cheapness may be largely 

 used. This anticipation has been realised. The modem 

 " kitchener," which, in so many forms is gradually and 

 steadily supplanting the ancient open range, is an appa- 

 ratus in which roasting in the open air before a fire is 

 superseded by roasting in a closed ^amber or roasting 

 oven. Having made three removals within the last twelve 

 years, each preceded by a tedious amount of house-hunting, 

 I have seen a great many kitchens of newly-built houses, 

 and find that about 90 per cent of these have closed 

 kitcheners, and only about 10 per cent are fitted with 

 open ranges of the old pattern. Bottle-jacks, like smoke- 

 jacks and spits, are gradually falling into disuse 



When these kitcheners were first introduced, a great point 

 was made by the manufacturer of the distinction between 

 the roasting and the baking oven ; the first being provided 

 with a special apparatus for effecting ventilation by devices 

 more of less resembling that in Rumford's roasting oven. 

 Gradually these degenerated into mere shams, and now in 

 the best kitcheners even a pretence to ventilation is aban- 

 doned. Having reasoned out my own theory of the con- 

 ditions demanded for perfect roasting some time ago (about 

 1860, when I lectured on " Household Philosophy " to a 

 class of ladies at the Hirmingham and Midland Institute), I 

 have watched the gradual disappearance of these conces- 

 sions to popular prejudice with some interest, as they show 

 how practical experience has confirmed this theory, which, 

 as already expounded, is that the meat should be cooked bij 

 the action of radinnl heat, jtrojected tov:ardis it from all 

 sides, while it is immersed in an atmosphere saturated witli 

 its own vapours. 



Herein I diverge from my teacher, as the preceding 

 description of both his roaster and roasting-oven shows. 

 His explanation of the prejudice of Englishmen against 

 baked meats may have been to some extent justified by his 

 own experience, seeing that he heated his ovens by a fire 

 placed below, and if he first used these without his water- 

 pan, they doubtless effected the decomposition of the 

 dripping and gravy of which he speaks (see No. XL of this 

 series, page 342) ; but even in this case the flavour of 

 merely burnt fat is not very serious — far less objectionable 

 than that of the vile mixture of vapours described in 

 No. X. 



The few domestic fireplace ovens that existed in 

 Rumford's time were clumsily heated by raking some of 

 the fire from the grate into a space left below the oven. 

 Those of the best modern kitcheners are heated by flues 

 going round tliem, generally starting from the top, which 

 thus attains the highest temperature. The radiation from 

 this does the " browning " for which Rumford's blowpipes 

 were designed. 



According to my view of the philosophy of roasting, this 

 browning, or the application of the highest temperature, 

 should take place at the beginning rather than the end of 

 the process, in order that a crust of lirnily coagulated albu- 

 men may surround the joint and retain the juices of the 

 meat AU that is necessary to obtain this effect in a suffi- 

 cient degree is to raise the roasting oven to its full tem- 

 perature before the meat is put in. Supposing an equal 

 fire is maintained all the while, this initial temperature 

 will exceed that of the continuing temperature, because, 

 when the meat is in the oven, the radiant heat from its 

 sides are intercepted by the joint and doing work upon it; 

 heat cannot do work without a corresponding fall of tem- 

 perature. While the oven is empty the radiations from 

 each side cross the open space to reinforce the temperature 

 of the other sides. 



Is there, then, any difference at all between roasting and 

 baking 1 There is. In roasting, the temperature, after 

 the first start, is maintained about uniformly throughout ; 

 while in baking by the old-fashioned method, the tempera- 

 ture continually declines from the beginning to the end 

 of the process ; but in order that a dweller in cities, 

 or the cook of an ordinary town household, may understand 

 this difference, some explanation is necessarj'. The old- 

 fashioned oven, such as was generally used in Rumford's 

 time, and is still used in country houses and by old- 

 fashioned bakers, was an arched cavity of brick with a flat 

 brick floor. This cavity is closed by a suitable door, which 

 in its primitive, and perhaps its best form, was a flat tile 

 that was pressed against the opening and luted round with 

 clay. Such ovens were, and still are, heated by simply 

 spreading on the brick floor a suflicient quantity of wood — 

 preferably well-dried twigs ; these, being lighted, raise the 

 temperature of the arched roof to a glowing heat, and that 

 of the floor in a somewhat lower degree. When this heat- 

 ing is completed (the judgment of which constitutes the 

 chief element of skill in thus baking) the embers are care- 

 fully brushed out from the floor, the loaves, ic, inserted 

 by means of a flat battledore with a long handle, called a 

 " peel," and the door closed and firmly luted round, not to 

 be opened until the operation is complete. Baked clay is 

 an excellent radiator, and therefore the surface of bricks 

 forming the arched roof of the oven radiates vigorously 

 upon its contents below, which are thus heated at top by 

 radiation from the roof, and at bottom by direct contact 

 with the floor of the oven. The ditt'erence between the 

 compact bottom crust, and the darker bubble-bearing top 

 crust of an ordinary loaf is thus explained. 



As the baking of a large joint of meat is a longer operation 

 than the baking of bread, there is another reason besides that 

 already given for the inferiority of meat when baked in a 

 baker's oven constructed on this principle. The slow cool- 

 ing-down must tend to produce a flabbiness and insipidity 

 similar to that of the roast meat which is served at restau- 

 rants where a joint remains " in cut " for two or three 

 hours. Of this I speak theoretically, not having had 

 an opportunity of tasting a joint that has been cooked 

 in a brick oven of the construction above described, but 

 have observed the advantage of maintaining a steady heat 

 throughout the process of roasting in the iron oven of a 

 kitchener, or American stove, or gas oven. 



