SMOKE BALLS. 



SMOKE j SMOKE PREVENTION. 



lYeparation* made rtmo are alao commendable. Mid for 

 long either a hydro-alcoholic compound fluid extract a good, 

 or UuTsatue brought to solid state, which diminishes the bulk, and 

 o fiu it for exportation. 



Tin- efficacy is sometime* heightened by the introduction of a small 

 quantity ..f liicliluride of mercury a very objectionable proceeding, u 

 a person taking mercury ignonntly, may expoae himself to cold and 

 run extreme risk of life. 



The curative power* of nnaparilla are often very much heightened 

 by combination either with alkalie*, especially lime-water, or in other 

 ea*en with acid*, particularly the nitric, Wh*n properly prepared, and 

 administered in cuitable cane, no one can doubt the efficacy of saraa 

 parilla. From the high price of it, and the great consumption, 

 attempt* hare been made in many of the great hospital* to dispense 

 with it or discover a cheaper cubntitute, but without success. In the 

 worn-out or debilitated syctems so common in the patients by whom 

 the** establishment* are crowded, it* utility is daily manifested. This 

 i* partly owing to the care taken to procure the beet kinds, and partly 

 to the appropriate u*e made of it, for the sake of economy. It is 

 chiefly used in chrome, syphilitic, rheumatic, gouty, and cutaneous 

 djaeaae*. It* most obvious action is diaphoretic, but if the patient be 

 kept cool, diuretic. In case* where an acid is indicated, the Hernidi*- 

 m<u MU/MW, which is possessed of a natural acid (hemidesmic acid), 

 will be found a useful substitute for the artificial preparations. 



If any European plant ever prove a proper substitute for sarsaparilla, 

 it will probably be the Tamtn communu, or black bryouy of our hedges, 

 the root of which, when scraped and applied externally as a poultice, 

 rapidly promote* absorption of effused blood. This U well known to 

 bruisers, gypsies, and others, who to remove ecchymoses of the eye 

 apply a poultice of this root, and generally remove the blackness in 

 twelve or twenty hour*. (Tyrrell ' On the Eye,' vol. i., p. 200.) 



A long list of plants used a* substitutes is given by Th. Martius in 

 hi* ' PharmakognoMe. In many cutaneous diseases petroleum will be 

 found quite as efficacious. It is far cheaper and taken in smaller 

 dose*. Pariglin, or smilacin has been recommended by Palotta, but 

 it has not come into much use. 

 , SMOKE BALLS. [LIGHT BALLS.] 



SMOKE ; SMOKE-PRK YKNTION. Smoke is the vapour arising 

 from substance* in a state of combustion. In its more extended sense 

 the word is applied to all the volatile products of combustion, which 

 consist of gawou* exhalations charged with minute portions of carbon- 

 aceous matter .or Boot ; but the term is frequently employed to express 

 the carbonaceous matter only. It is important to bear this distinction 

 in mind, as it involves a fact which appears to have been sometimes 

 overlooked : namely, that however completely the soot may be 

 destroyed, and the smoke be thereby rendered invisible, it still remains 

 necessary to provide means of free exit for the deleterious gases. 

 The action of an ordinary chimney in conveying the smoke from a 

 fire situated at its lower extremity is very simple. The air in the 

 chimney, being rarefied by the heat, becomes lighter in proportion to 

 its bulk than the surrounding atmosphere, and therefore rises: its 

 place being supplied by fresh air forced in at the lower end by the 

 pressure of the comparatively heavy cold air outside the chimney. A 

 constant rising current is thus created, the force of which is sufficient 

 to carry up with it any light bodies, such as the particles of soot which 

 escape from the fire. The intensity of this current depends much 

 upon the height of the chimney ; for it is evident that the higher a 

 chimney is, within reasonable limits, the greater must be the difference 

 between the weight of the column of hot air which it contains, and 

 that of a column of cold air of equal elevation. It is also evident that 

 the hotter the air in the chimney is kept, the more rapidly it will rise. 

 Hence chimneys act better when built in stacks, or when in the 

 interior of a house, than when single, or when outside the walls. 



The circumstances which impede the proper action of chimneys, and 

 occasion the annoyance of smoke in houses warmed by common open 

 stoves, have excited the attention of many individuals, and formed the 

 subject of several treatises. Franklin analysed the subject very 

 judiciously, and published a pamphlet pointing out nine causes, or 

 kinds of cause, for the evil. 1 . The want of a free supply of air to 

 the bottom of the chimney. It is of little consequence how spacious 

 the room may be into which the chimney opens, if the access of fresh 

 air to the room be cut off. As the hot air escapes from the top of the 

 chimney, its place must be filled by fresh air taken from the room. 

 But if the entrance of the external atmosphere be insufficient, every 

 chimney-full of air abstracted from the room lessens the density of what 

 remains, so that the draught will decrease until the air in the chimney 

 and that in the room are of equal density ; after which it will cease 

 altogether, and the smoke will no longer ascend. This inconvenience 

 can only be remedied by providing openings for air commensurate to 

 the demand* of the fire. Whenever it is practicable, the best situation 

 for them i* near the top of the room, and over the fire-place ; because 

 the entering air is then warmed by the warm air which rise* to the top 

 of the room, and becomes pretty generally diffused. The object may 

 1* attained by leaving a window a little open at the top, or by pro- 

 viding long narrow opening" above the window or immediately beneath 

 the cornice. Another plan i* the use of a pane of glass in the window, 

 hinged to the frame at it* lower edge, and capable of being opened 

 more or leas a* required ; ride-pieces of glass being added to prevent 



the. air from entering laterally. Sometime* a number of strips of 

 plate-glass, so arranged a* to rewmble a Venetian blind, are used ; 

 these (being so placed a* to throw the air upwards. The common 

 ventilator, or vkirligig, answers the same purpose, and diffuses the air 

 in some degree by its rapid revolution, occasioned by the action of the 

 current upon it* inclined vanes. 2. Many chimney* smoke because 

 the opening at the lower end is too large. While a small opening to a 

 tall chimney increases the draught to an improper degree, and causes a 

 wasteful consumption of fuel, a large opening to a abort funnel will 

 allow the smoke to escape into the room ; because all the air required 

 by the chimney may enter at one side of the opening, leaving the other 

 nide free from current, and therefore allowing the smoke to puff out. 

 In such a case the draught is weakened by the coldness of tli. air 

 which enters the chimney at such a distance from the fire a 

 very little affected by it. This defect must be remedied by contracting 

 the opening. 3. A third cause of defective action is the funnel or 

 chimney being too short. The game effect i* produced when the flue 

 from an upper story is turned into one from a lower room. The 

 inconvenience of such an arrangement may be somewhat diminished 

 by a contrivance for closing the collateral flue when not in use. The 

 shortness of a chimney may sometimes be rendered harmless by con- 

 tracting the entrance, so that all the air entering it skill be highly 

 heated, by passing immediately over the fire. 4. Different chimneys 

 in the same house occasionally overpower each other. If we suppose 

 two stoves, each having a distinct chimney, in a room without a 

 sufficient supply of air from without, we may conceive that one fire 

 becoming stronger than the other, may overpower it, and obtain a 

 supply of air down the chimney of weakest draught ; the descending 

 current of course blowing the smoke of the weaker flue into the room. 

 Precisely the same effect will take place if the stoves are in different 

 rooms ; provided there be, owing to the opening of the doors, a com- 

 munication between them. This will account for the common case of 

 a parlour chimney smoking whenever the room-door is opened, 

 although it may act properly when the room is closed, and thereby 

 cut off from the effect of the kitchen chimney. The proper cure is 

 clear ; if every room have a free supply of air from without, there 

 will cease to be any probability of the chimney of one apartment over- 

 powering that of another. 5. Another cause arises from the situation 

 of the house. If a house stand under the brow of a hill, or in the 

 vicinity of a much higher building, the wind, passing over the higher 

 obstacle, beate down into the chimneys of the sheltered house, and so 

 prevents the exit of smoke. This may sometimes be remedied by 

 raising the chimney, and in other cases by means of a cowl, or turning- 

 cap, the opening of which always turns from the wind. The ordinary 

 cowl is turned by means of a vane attached to its upper part ; but one 

 patented by Mr. Pollard is turned by wheels set in motion by the 

 action of the wind upon the oblique vanes of a rotatory flyer. Another 

 contrivance consists of a square box placed on the top of the chimney, 

 each side of which is a door, hinged at one edge, and connected, by 

 means of an iron rod, with the door on the opposite side of the box : 

 in such a way that when one door is closed by the force of the 

 wind, the opposite one opens, and allows the smoke to escape. 

 6. Chimneys occasionally smoke from a cause just the reverse of that 

 last described. This occurs when the chimneys ore low, and stand 

 between the wind and a high building, or neighbouring edifice, so that 

 the air is dammed up, as it were, round about them. Raising the 

 chimneys appears to be almost the only alternative. 7. Another cause 

 of smoking is the injudicious arrangement of the door or doors of a 

 room. If the door be on the same side as the fire-place, and occasion 

 it to smoke by sending a current across the front of the stove, either it 

 must be altered so as to open in the opposite direction, or a screen 

 must be used between it and the stove. 8. Smoke is sometimes blown 

 down a chimney which is out of use. This arises from the circum- 

 stance that a stock of chimneys usually maintains a more uniform 

 temperature than the surrounding air. When in the middle of the 

 day, the air generally becomes warmer than that in the chimneys, the 

 current moves downward, carrying with it smoke that may happen to 

 be passing over, or escaping from a neighbouring flue. A "plate or 

 register, closing the bottom of the chimney when out of use, obviates 

 this inconvenience. 9. Chimneys, which under ordinary circumstances 

 perform very well, occasionally smoke in consequence of the passage of 

 \ strong wind over them, which the force of the rising vapour is 

 insufficient to cope with. Among various modes of cure adopted, one 

 is to moke the top of the flue funnel-shaped, with a view to facilit.it r 

 the escape of the smoke under such circumstances ; another, to reduce 

 the opening at the top to a long narrow slit. Probably a cowl might 

 be of use in such a case. 



The nuisance occasioned by the smoke of coal-fires has formed a 

 subject of complaint from the earliest times in which mineral fuel was 

 extensively used; and the great increase of steam-engine and other 

 Furnace*, consequent on the extension of manufactures, lias afforded, of 

 late years, additional ground for attempts to abate the nuisance. Such 

 attempts are important, not only for the purification of the air, but 

 also for the economy of fuel ; since the matter which gives smoke 

 objectionable density and colour is unconsumed fuel in a finely-il i 

 state. It appears, therefore, that if a supply of air could be thrown 

 into a fire in such a way, as to occasion the combustion of the carbona- 

 ceous matter, the result would be that a greater amount of heat would 



