Scientific American, Vol. XXXVII.—No. 2. [New Series.], July 14, 1877 A Weekly Journal of Practical Information, Art, Science, Mechanics, Chemistry, and Manufactures

Part 5

Chapter 54,153 wordsPublic domain

Instead of measuring the lead of the valve with a rule, or by a wedge, the following plan is very often adopted: After the valve and spindle are in position, the valve is placed with the proper amount of lead upon the front port. A center punch mark is then made upon the face of the steam chest. A piece of quarter inch iron wire is then bent at right angles and each end filed to a point. One end of this wire is placed in the fixed center punch mark in the steam chest, and with the other a mark is made upon the slide spindle. Upon this latter mark a center punch mark is also made sufficiently deep to be very plainly visible when the burr raised by center punching is filed off, which is necessary to prevent this burr from cutting the packing. It follows that whenever the bent piece of wire will rest with one end in the center punch mark in the steam chest, and the other end in the center punch mark in the slide spindle, the valve is in its proper position when the crank is on the corresponding dead center. This plan is a very old one and possesses the advantage that the valve may be set without seeing it, that is to say, with the steam chest cover on. If the length of the piece of wire measured direct from point to point is known, the valve may be set when the engine is upon the road without taking off the steam chest cover. The center punch mark upon the steam chest should, however, always be placed in about the same spot, so as to avoid mistakes in case of there being other similar marks upon the chest. It should always be made deep, so as not to get filled up with paint and be difficult to find. In course of time the mark upon the slide valve spindle is apt to disappear from the wear of the spindle, hence the center punch with which it is made should have a long conical point. To mark the position of the eccentric upon the axle, it is an excellent plan, after the eccentrics are finally adjusted, to take a chisel with the cutting end ground to the form of a fiddle drill, one cutting edge being at a right angle to the other. The chisel must be held so that while one edge rests upon the axle, the other edge will bear against the radial face of the eccentric. A sharp blow with a hammer upon the chisel-head will make a clean indented cut upon the axle and the eccentric, the two cuts exactly meeting at their junction and denoting the position of the eccentrics. In setting the valves of inside cylinder locomotives, the back ports being out of sight, the amount of lead is ascertained by making a wooden wedge about three inches long, a thirty-second of an inch thick at one end and three eighths of an inch thick at the other end. The faces of this wedge are chalked, and the lead is measured by inserting it between the edge of the valve and the edge of the port until its thickness just fills the space, and then moving it edgeways so that the valve and port edges will just mark it. By measuring the thickness of the wedge at the mark, the amount of lead is ascertained. After the valves are set, it is still desirable to mark the position by center punch marks upon the outside of the steam chests and upon the valve spindles, as already described.

If an eccentric should slip when the engine is upon the road, and there are no marks whereby to readjust them, it may be done approximately as follows: Put the reverse lever in the end notch of the forward gear, then place the crank as nearly on a dead center as the eye will direct, and open both the cylinder cocks, then disconnect the slide valve spindle from the rocker arm, and move the valve spindle until the opening of the port corresponding to the dead center on which the crank stands will be shown by steam blowing through the cylinder cock, the throttle valve being opened a trifle. The position of the valve being thus determined, the eccentric must be moved upon the shaft until the valve spindle will connect with the rocker arm without being moved at all. The throttle valve should be very slightly opened, otherwise so much steam will be admitted into the cylinder that it will pass through any leak in the piston and blow through both cylinder cocks before there is time to ascertain which cock gives first exit to the steam.

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NEW STEAMER.

A new steamer for the Mallory line, between New York and Texas, was lately launched from the yard of Roach & Co., Chester, Pa., 2,200 tons burden. Principal dimensions as follows: Length over all, 239 feet 7 inches; beam (moulded), 34 feet; depth from the base to the spar deck beams, 18 feet 2½ inches; depth of hold, 16 feet 5½ inches; diameter of propeller (Hirsch's patent-four blades), 11 feet 6 inches. She is to be provided with compound engines, having cylinders 24 and 44 inches in diameter, with a stroke of 44 inches, and two return tubular boilers 10 feet long, 10 feet 3 inches wide, and 8 feet 6 inches high. Aft are compartments capable of holding 80 tons of water, for the purpose of depressing the stern before and after crossing the bar at Corpus Christi. Her low draught is 7½ feet; speed, 14 knots.

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A TIN-CAN TELEPHONE.

In Professor Bell's telephone a plate of sheet iron is made to vibrate by means of the electrical current, something after the manner of the skin of a drumhead. In a recent improvement by Mr. G. B. Havens, Louisville, Ky., the electrical wires are wrapped around a common tin fruit can. By means of tin cans at each end, sounds, it is said, were sent over 92 miles of wire, and included several pieces of music.

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MR. HOTCHKISS, an American inventor, whose improved revolving cannon we illustrated some time since, has received intimation that his system has been approved by the French Government, and that they have decided to adopt his cannon.

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COLLENDER'S IMPROVED BILLIARD TABLE.

In the accompanying engravings, we illustrate two important improvements in the construction of billiard tables, which have recently been devised by Mr. H. W. Collender, the well known billiard table manufacturer of this city. The first, which is represented in Fig. 1, relates to the construction of the bed-supporting frame, and aims to render the same stronger while cheapening its manufacture. In putting together the body and framework of the table, the usual practice is to cut away the stock of the cross beam and longitudinal beam, and halve them together. Longitudinal grooves are also formed on the inner surface of the side and "broad rails," to accommodate tenons on the ends of the cross beams; and the latter are secured in place by bolts fastening their ends to the broad rails. Mr. Collender claims that, by this mode of construction, not only are the cross beams weakened by being halved together, but the broad rails are also weakened by the cutting away of this stock near the middle to effect the framing into them of the ends of the cross beams.

From Fig. 1, it will be seen that the cross beam, A, is combined with the side broad rails in the following manner: Upon the inner face of each broad rail is secured a cast iron socket piece, B, into which fits one end of the cross beam, A. From said beam the bolt, C, passes through the shoe, B, and is secured by a nut, D, let into the stock of the broad rail. The shoe, B, has lugs which enter the broad rail; and the aperture in it, through which the bolt passes, is made oblong to admit of the drawing of the parts together after the insertion of the bolt. Upon the sides of the cross beam near the middle, and directly opposite each other, are two shoes, E; these have no bolt holes. In them are placed the adjacent ends of the longitudinal beams, F, the other extremities of which are seated in shoes on the broad rails. The shoes, E, have their lugs of such a length, compared with the thickness of cross beam, A, that when put in place on said beam said lugs will come together. The advantage of this is that, should the beam, A, shrink in width, the shoes on each side of it will still maintain their proper relation to form immovable abutments for the ends of pieces, F. This construction allows of shorter stuff being used in the manufacture, and renders the framework stronger.

In Fig. 2 is illustrated a new method of forming the corners of the table. Hitherto it has been customary to use corner blocks, of various sizes according to the dimensions of the table, located one at each corner. Into these the broad rails were framed and secured. To this arrangement Mr. Collender adduces a long category of objections, based on the possibility of the weight of the bed being thrown on these blocks in case of shrinkage of the frame, on the fact that the corner of the table bed must necessarily be left without any support where it extends over the upper end of the corner block, and also that in a bevel table, in which the area of the top of the corner block is unavoidably much greater than that of the top of the corner block of a vertical-sided table, a large portion of the table bed will be left without any support.

The new device consists of a cast iron union plate, G, which is bolted to the leg as shown. The broad rails and casting are securely fastened by the bolt, H. It will be seen that this bolt, passing through the end of one broad rail, and into a nut let into the other rail, will securely draw and hold together the ends of said rails and the interposed metal plate clamped between them, and that as the plain ends of the wooden rails just fit (widthwise) between the projecting heads on the edges of said interposed plate, the latter will form a sort of housing for the ends of the rails. And it will be understood that in this construction not only does the bead on the outer edge of the plate overlap the edges of the rails and form a neat and durable corner finish to the body, but the broad rails being bolted together in the direction of the grain of the wood with only an interposed metal plate, there will be no tendency to a loosening of the union of the parts of the frame. The main importance of this invention rests in the idea of dispensing with the usual corner blocks, and thus permitting the top edges of the broad rails, on which the bed rests, to practically come together and afford a perfect support to the bed clear out to the corners of the latter; at the same time the whole structure is rendered stronger and more durable with less weight of material.

These inventions are the subject of separate patents, that of the first being dated April 4, 1876, and of the second, November 16, 1875. For further information, address the manufacturer and patentee, Mr. H. W. Collender, 738 Broadway, New York city.

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COATING ENGRAVED COPPER PLATES WITH STEEL.

In order to render copper plates which are used in printing more durable, they can be covered with an electrolytic deposit of iron which possesses an unusual degree of hardness almost superior to steel. The salt usually employed has been the double sulphate of iron and ammonia. Professor Böttger, who first invented this process, has recently devised an improvement in the bath employed. He dissolves 10 parts of ferrocyanide of potassium (yellow prussiate of potash) and 20 parts of the double tartrate of soda and potash (Rochelle salts) in 200 parts of water, and to this he adds 3 parts of persulphate of iron dissolved in 50 parts of water. A large precipitate of Prussian blue is formed. To the whole is added, drop by drop, with constant stirring, a solution of caustic soda until the blue precipitate entirely disappears, leaving a perfectly clear, light yellow liquid, which is now ready for use.

Professor Böttger also claims that this solution can be employed with advantage for dyeing cotton yarn and fabrics a beautiful blue, without the use of a mordant. For this purpose the goods are put into the bath, that has previously been slightly warmed, until they are saturated through and through, and then dried in the air, after which they are immersed in extremely dilute sulphuric acid (1 to 50), which neutralizes the alkali, and after washing and drying again they are permanently dyed a fine blue color.

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TEST FOR SULPHUR IN ORGANIC COMPOUNDS.

H. Vohl recommends the following as the best method of detecting sulphur in organic compounds: The substance to be tested is heated in a solution of caustic lime and oxide of lead in glycerin. The latter is prepared as follows: One volume of distilled water is mixed with 2 volumes of pure glycerin and heated to boiling; freshly prepared slaked lime is added, little by little, until it is saturated. Freshly precipitated hydrated oxide of lead, or moist litharge, is added in excess, and the liquid allowed to boil gently for a few minutes, then tightly corked and left to cool, after which the clear liquid is decanted from the sediment into a glass vessel that can be tightly corked. If into this solution be introduced and heated any organic which contains sulphur, like hair, feathers, horn, albumen, and the like, it will at once turn black from the formation of sulphide of lead. The great delicacy of this test is evident from the fact that, when pure wheat bread is boiled with this reagent, it turns yellow at first and then dark gray in consequence of the presence of sulphur in the gluten of the bread.

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IMPROVED BILLIARD BALL HOLDER.

The usual receptacle for the fourth ball, when only three balls are used in the game of billiards, is placed at the side of the table. As this is both inconvenient and unsightly, a neat device, clearly shown in the annexed illustration, has been invented, which is intended to be attached to a gas fixture over the table. A plate or sign is also added on which the number of a table--in case several tables are employed, as in a billiard saloon--may be inscribed. The form and design of the arrangement may of course be varied in many ways.

Patented May 2, 1876. For further particulars, address the manufacturer, Mr. H. W. Collender, 738 Broadway, New York city.

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THE MONITOR CHALK CUP.

The annexed engraving represents an improved chalk cup or holder for billiard tables, which is so constructed that it will not become loose, sag down, mar the table, or jar when the ball strikes the cushion. It may be adjusted to remain in any desired position.

The shank is pivoted in a metallic frame which is secured to the table. The rear end of the shank works against a spring. On the upper portion of the shank is a projection which embraces a horizontal flange to sustain the box against being forced downward. The arrangement is very similar to the ordinary window catch. The player has only to start the box from its position under the table, when the spring carries it out at right angles to the rail. A touch is sufficient to cause the spring to carry the box back to its former position. The device is very simple, and its advantages will be evident to all billiard players cognizant of the defects of the ordinary cup.

Patented May 1, 1877. For further particulars, address the manufacturer and patentee, Mr. H. W. Collender, 738 Broadway, New York city.

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CURIOUS CARNIVOROUS PLANTS.

The _arum Dracunculus_ is one of the most curious of that wonderful series of carnivorous plants which at the present time are engaging the closest scrutiny of naturalists. It is a true trap in one sense--inasmuch as it captures the victim which ventures near it; but it relies on little or no mechanical means for securing its prey, but stupefies the living insect by its odor. The flower is horn-shaped, about 11 inches in length, with an opening some 5 inches in diameter. The color within is a dull dark violet, while the interior of the spathe is lined with black, hooked bristles, the whole appearance of the flower being thoroughly repulsive. The illustrations herewith presented, Figs. 1 and 2, represent it at one third its natural size, Fig. 2 showing a section of the flower. It is not certain what attracts the insects, which are usually of the species known as the meat fly and the common house fly. They do not seem to seek for the small quantity of nectar concealed, and yet they cluster about the fatal opening, as if drawn by some overpowering fascination. Overcome by lethargy, they fall inert upon the flower, are lightly held by the bristles, and finally die asphyxiated by the carbonic acid which the plant disengages in large quantities during its inflorescence. Strange as is the action of the _arum_, the method whereby the _mentzelia_ takes its prey is even more wonderful. To illustrate on a magnified scale, let the reader imagine a surface thickly covered with strong iron posts, on the sides of which are numerous keen barbs pointing downward. Then between these posts, suppose that jars overflowing with honey are placed. An elephant, let it be imagined, attracted by the profusion of sweetness, inserts his trunk between the posts and finds easy access to the honey. But while he can force his proboscis downward past the barbs turned in that direction, when he attempts to withdraw it he finds the keen points catch in the flesh, and render it impossible to do so. A terrible struggle follows, the unfortunate animal twisting and writhing in every direction, until finally by an Herculean effort the head is torn from the body, and the latter becomes digested by some potent gastric juice, exuding from the colossal organism of which the trap forms but a portion. Of course this is vastly exaggerated, and it would puzzle an elephant to pull his own head off; but if for the post studded trap, we substitute the surface of a flower, and if we replace the elephant by a fly, we shall have conceived an accurate picture of what takes place in the peculiar receptacle with which Nature has provided the _mentzelia ornata_. This is very beautifully shown in Fig. 3; and at A, in same figure, is represented the barbed bristles grasping the highly magnified proboscis of the fly. Between the barbed bristles are mushroom-shaped projections, from the summits of which a viscous nectar exudes. This is the honey bait which induces the insect to insert his trunk between the fatal barbs. There is still another plant, _physianthus albens_, which captures butterflies by grasping the proboscis. The construction of the flower is quite complicated, so that the insects are compelled to insert their trunks through a narrow and winding passage in order to reach the nectar. The organ then necessarily comes in contact with an adhesive substance, which prevents its removal.

The _Gronovia scandens_, Fig. 4, is another plant trap, which catches no flies nor possesses any such wonderfully adapted devices as the plants already described. It simply has its branches covered with double barbed bristles of great strength which attach themselves to anything brought in contact with them. The bristles are strong enough to hold lizards, as represented by our engraving, the points inserting themselves in the interstices of the scaly covering of the reptile. Of course the lizard thus held starves to death, and small birds often follow a like fate. We are indebted to _La Nature_ for the illustrations.

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POPULAR FALLACIES.

Night air and damp weather are held in great horror by multitudes of persons who are sickly or of weak constitutions; consequently, by avoiding the night air, and damp weather, and changeable weather, and weather that is considered too hot or too cold, they are kept within doors the much largest portion of their time, and as a matter of course continue invalids, more and more ripening for the grave every hour; the reason is, they are breathing an impure atmosphere nineteen-twentieths of their whole existence.

As nothing can wash us clean but pure water, so nothing can cleanse the blood, nothing can make health-giving blood, but the agency of pure air. So great is the tendency of the blood to become impure in consequence of waste and useless matters mixing with it as it passes through the body, that it requires a hogshead of air every hour of our lives to unload it of these impurities; but in proportion as this air is vitiated, in such proportion does it infallably fail to relieve the blood of these impurities, and impure blood is the foundation of all disease. The great fact that those who are out of doors most, summer and winter, day and night, rain or shine, have the best health the world over, does of itself falsify the general impression that night air or any other out-door air is unhealthy as compared with in-door air at the same time.

Air is the great necessity of life; so much so, that if deprived of it for a moment, we perish; and so constant is the necessity of the blood for contact with the atmosphere, that every drop in the body is exposed to the air through the medium of the lungs every two minutes and a half of our existence.

Whatever may be the impurity of the out-door air of any locality, the in-door air of that locality is still more impure, because of the dust, and decaying and odoriferous matters which are found in all dwellings. Besides, how can in-door air be more healthy than the out-door air, other things being equal, when the dwelling is supplied with air from without?

To this very general law there is one exception, which it is of the highest importance to note. When the days are hot, and the nights cool, there are periods of time within each twenty-four hours, when it is safest to be in-doors, with doors and windows closed; that is to say, for the hour or two including sunrise and sunset, because about sunset the air cools, and the vapors which the heats of the day have caused to ascend far above us, condense and settle near the surface of the earth, so as to be breathed by the inhabitants; as the night grows colder, these vapors sink lower, and are within a foot or two of the earth, so they are not breathed. As the sun rises, these same vapors are warmed, and begin to ascend, to be breathed again, but as the air becomes warmer, they are carried so far above our heads as to be innocuous. Thus it is that the old citizens of Charleston, S. C., remember, that while it was considered important to live in the country during the summer, the common observation of the people originated the custom of riding into town, not in the cool of the evening or of the morning, but in the middle of the day. They did not understand the philosophy, but they observed the fact that those who came to the city at mid-day remained well, while those who did so early or late suffered from it.

All strangers at Rome are cautioned not to cross the Pontine marshes after the heat of the day is over. Sixteen of a ship's crew, touching at one of the West India islands, slept on shore several nights, and thirteen of them died of yellow fever in a few days, while of two hundred and eighty, who were freely ashore during the day, not a single case of illness occurred. The marshes above named are crossed in six or eight hours, and many travelers who do it in the night are attacked with mortal fevers. This does, at first sight, seem to indicate that night air _is_ unwholesome, at least in the locality of virulent malarias, but there is no direct proof that the air about sunrise and sunset is not that which is productive of the mischief.

For the sake of eliciting the observations of intelligent men, we present our theory on this subject.