Various

“ There is, fortunately, no necessity for being idle, or to relinquish photographic pursuits entirely, even though the weather and light combine to render out-door work almost impracticable; and most amateurs will be found to have some hobby or favorite amusement which enables them to keep in practice during those months when many channels of employment are closed to them; and probably one of the most popular as well as the most pleasing occupations is the production of transparencies for the lantern. ”

“ Many seem to think that it is only necessary to have a hole somewhere in the boiler—no matter what part—through which water may be pumped, and we have all that is desired. This is a very grave error. Many boilers have been ruined, and (we make the assertion with the confidence born of long experience) a large number of destructive explosions have been directly caused by introducing the feed water into boilers at the wrong point. ”

“ The invention of a self propelling engine, capable of working without fuel economically and for a considerable time, has often been attempted, and was, perhaps, never before so nearly accomplished as about the time of the introduction into practical use of Faure's electric storage batteries; but at the present moment it appears that electric power has to give way once more to steam power. ”

“ Although the manufacture of soluble glass does not strictly belong to the glass maker's art, yet it is an allied process to that of manufacturing glass. Of late soluble glass has been used with good effect as a preservative coating for stones, a fire-proofing solution for wood and textile fabrics. Very thin gauze dipped in a solution of silicate of potash diluted with water, and dried, burns without flame, blackens, and carbonizes as if it were heated in a retort without contact of air. ”

“ Honigmann's invention of the fireless working of steam engines by means of a solution of hydrate of soda—NaO HO—in water is not quite two years old, and has in that time progressed so steadily towards practical success that it is reasonable to expect its application before long in many cases of locomotion where the chimney is felt to be a nuisance. The invention is based upon the discovery that solutions of caustic soda or potash and other solutions in water, which have high boiling points, liberate heat while absorbing steam, which heat can be utilized for the production of fresh steam. ”

“ No really well informed person has believed for a long time that carbolic alcohol will destroy the cholera poison; but many fully and correctly believe that real germicides will. It has been known since 1872 that microbes, bacilli, and bacteria could live in very strong solutions of carbolic alcohol, and that the dilute mineral acids, tannin, chloride, corrosive sublimate, and others would kill them. ”

“ In fact, it appeared from experiment that the dose of carbon might with advantage be so great as not only to be itself oxidized into carbonic oxide by the oxygen of the nitro-glycerine, but to reduce the carbonic acid developed by the explosion of the latter itself into carbonic oxide. ”

“ Every mosque has a public privy, and also a tank for the ablution, which all good Mohammedans must use before entering a holy place. There was, of course, great choleraic water contamination, and a sudden outburst of cholera took place. The 15,000 people who came to the fair were stampeded out of Damietta, together with about 10,000 of the inhabitants, who carried the disease with them back into Egypt. Then only was a rigid quarantine established, and a cordon put round Damietta to keep everybody in, and let no one go out, neither food, medicines, doctors, nor supplies of any kind. ”

“ It is a favorite method to connect the feed pipe, F, to the end of the mud drum which projects through the wall, and here the feed water is introduced, whether hot or cold; and there is really not so much difference after all between the two, for no matter how effective a heater may be, the temperature to which it can raise water passing through is quite low compared with the temperature of the water in the boiler due to a steam pressure of say eighty pounds per square inch. The difference in the effect produced by feeding hot or cold water at the wrong place is one of degree, not of kind. ”

“ Those who have never made a transparency will have doubtless printed silver prints from their negatives, and when printing, how often do you find that to secure the best results you require to have recourse to some little dodge. ”

“ Experiments in regard to the relation between chemical composition and strength of the material have established that a large amount of silicium, graphite, manganese, and combined carbon reduce the elasticity, strength, and tenacity of cast iron, and that a limited percentage of silicium counteracts the injurious influence produced by an excess of combined carbon. On remelting of cast iron, increase in tensile strength was observed, which attained its maximum in iron with a small percentage of silicium after the third, and in such with a large amount after the fourth melting. ”

“ I take a piece of card-board and gum it on to the glass side of the negative, and this addition gives me a size that lends itself easily to reduction to the lantern disk, and in no way detracts from the picture.
Having said so much about making up the size, let me add a few words as to other preparations that are sometimes necessary. In a good lantern transparency, it is, of all things, indispensable that the high lights be represented by pure glass, absolutely clean in the sense of its being free from any fog or deposit, to even the slightest degree ”

“ Subcutaneous injections of large quantities of salt and water, with some soda, and large rectal injections of tannin and laudanum have been very successful in Italy. If there is plenty of acid gastric juice in the stomach, the cholera poison and microbes may be swallowed with impunity. The worst cases of cholera are produced by drinking large quantities of cholera contaminated water, when the stomach is empty and alkaline. I think it probable that large quantities, as much as the thirst requires, of a weak acid water will prove very beneficial in cholera. ”

“ Proof is therefore given that the soda engine has a working capacity which is at least equal to that of the coal burning engine. The heating surface of the soda engine, moreover, is 85 square meters, while that of the corresponding new Henschel engine is 92 square meters. On a former occasion I have already stated that the soda engine is capable not only of performing powerful work and of producing a large quantity of steam during a short time, but also of travelling long distances with the same quantity of soda. ”

“ Now, let us bear this in mind when using such a negative for the printing of a transparency, for, as I have said before, it is only a process of printing, after all. Although we cannot, when using a sensitive plate, employ the same means of dodging as in the case of a silver print, still we are not left without a means of obtaining the same results in a different way, and this just brings me to what I have already hinted at previously, that a deal more depends on the manipulative skill of the operator than in the adoption of any particular make plate or formula ”

“ The horizontal component of the greatest stress in any diagonal, which will be both compressive and tensile, and is the same for every diagonal brace in the girder, is equal to the amount of the live load per bay multiplied by the span of the girder, and divided by sixteen times the depth of girder at center. ”

“ You will at once understand that a negative whose size bears a proportion similar to 31⁄4 by 31⁄4 will lend itself more easily to reduction; thus whole plate or half plate negatives are easy of manipulation in this respect, and require but little doing up. But as other sizes have at times to be copied into a disk1⁄4 by 31⁄4, recourse must be had to a sort of squaring of the negative. Now, here I have a negative 71⁄4 by 41⁄2, which is perhaps the worst of all sizes to compress into the lantern shape, so I have, as it were, to square this negative, and this I do by simply adding to sky. ”

“ From trials conducted by Ledebur, it appears that cast iron is rendered suitable for foundry purposes—i.e., to fill the moulds well and to yield sharp and definite forms free of flaws, to be cut with a chisel, and turned on a lathe—through a certain percentage of graphite, whose presence depends on that of carbon and silicium. ”

“ In order to obtain a complete combustion of the flowers of sulphur, it is necessary to see to it that the burning is effected equally over its entire surface, this being easily brought about by moistening the sulphur with alcohol and then setting fire to the latter. Through the use of this process a complete and absolute combustion has been obtained of much as from 18 to 20 grains of sulphur per cubic foot.
In the proportion of 8 grains to the cubic foot, all the different culture broths under experiment were sterilized save the one containing the bacteria of charbon. ”

“ Billroth is a master of surgical technique, and his courage and composure increase with the difficulty of the operation. He always makes use of the most simple apparatus and instruments, and follows a theoretically scientific course which he has never left since he adopted surgery as a profession, and by which he has directed surgery into entirely new channels. ”

“ Although the racing of steam yachts as a recognized sport has not made the progress that was at one time expected, yet the owner and crew of a crack vessel will take as much interest in her performance as those belonging to a sailing yacht, and hate to be passed quite as badly. ”

“ I nearly always block out my skies, and so strengthen the other parts of my negatives, that I can rely on a full exposure without fear of heaviness or smudginess. This blocking out is easily done.
Haying said so much about the preparation of the negative, let me now describe the apparatus I use. I have here an ordinary flat board, and here my usual camera; it is the one I use both for outside and inside work. It is a whole-plate one, very strongly made, and has a draw of twenty-three inches when fully extended ”

“ On the location and construction of the feed depends to some extent the economical working of a boiler, and, to a great extent, especially with certain types of boilers, its safety, durability, and freedom from a variety of defects, such as leaky seams, fractured plates, and others of a similar kind. And it is unfortunately true that the type of boiler which from its nature is most severely affected by mal-construction, such as we are now speaking of, is the very one which is the oftenest subject to it. ”

“ It is very generally considered that it is better the glasses receive either a substratum of albumen or very weak gelatine. I use the latter on account of the great ease of its preparation. After your glasses are well cleaned, place them in, and rub them with a weak solution of hydrochloric acid of the strength of 2 ounces acid to 18 ounces water.
Prepare a solution of gelatine 1 grain to the ounce of water, rinse the plate after removal from the acid mixtures, and coat twice with the above gelatine substratum; the first coating is to remove the surplus water, and should be rejected. ”

“ The current is interrupted by means of a small vibrating device whose mode of operation may be easily understood by glancing at the section in Fig. 2. The current enters the electro-magnet through a fine copper wire hidden in the leaves and connected with the positive pole of the pile. The negative pole is connected with the bottom of the pot. The wire from the vibrator of each insect reaches the bottom of the flower-pot, but does not touch it. A drop of mercury occupies the bottom of the pot, where it is free to move about. ”

“ The making of a really good transparency is by no means an easy or pleasant task with a wet collodion plate, but with these dry plates an amateur can, with a little practice, produce comfortably slides quite equal to those procurable from professional makers. ”

“ Any bends in the conduit affect the result to a very slight degree, and the ventilator may be used with advantage when the conduit is divided as in Fig. 4, in order to get the fresh air to different points. The ventilators are easily fixed to the air conduits. If they are to be connected to zinc air pipes, the pipe is simply slipped over the point, L. in Fig. 1, and if to wooden conduits the apparatus is simply put into them, and if no other support is required. Furthermore, they are so light that it suffices for one man to fix them or change their position. ”

“ SULPHUROUS ACID AND SULPHIDE OF CARBON.
Much attention has been paid in recent times to disinfecting agents, and among these sulphurous acid and sulphide of carbon must be placed in the list of the most efficient. Mr. Alf. Riche has recently summed up in the Journal de Pharmacie et de Chimie the state of the question as regards these two agents, and we in turn shall furnish a few data on the subject in taking the above named scientist as a guide. ”

“ One of the most difficult problems that daily presents itself in large cities is how to proceed without danger in the search for leakages in gas mains, or in attempts to save life in houses accidentally filled with explosive gases. ”

“ I then transferred the weighed sample to the crucible, the melted potash in which readily wetted the graphite rock. The mass was then gently heated, and occasionally stirred with a piece of silver wire. The heat never need be much above the melting point of the potash, though toward the last I have been in the habit of raising the temperature slightly, to insure the complete decomposition of the melt. ”

“ It appears that after a certain fire in a manufactory at Berlin, the police authorities issued notices concerning the use of cast-iron columns in high buildings, and that these notices encountered great opposition in many quarters, as it was considered that neither practice nor theory had yet shown any proof that cast iron is less trustworthy than wrought iron in cases of fire. ”

“ It takes about five and a half pounds for a room of 3,500 cubic feet capacity. The process is sure and quite economical, since sulphide of carbon is sold at about five cents per pound, which amounts to 25 cents for a room of 3,500 cubic feet capacity. The burner costs ten dollars, but may be used for an almost indefinite period.
The process of producing sulphurous acid by the combustion of sulphide of carbon is, as may be seen, very practical and advantageous. It does not affect metallic objects, and it furnishes a disinfecting gas continuously, slowly, and regularly. ”

“ He concludes that the rise of a column of warm moist air into the colder atmosphere above will be followed by a thunderstorm if it acquires sufficient velocity to prevent neutralization of the electricity generated by the friction of the air. Hence, in his opinion, open districts denuded of forests are more liable to thunderstorms than wooded regions, where the trees forbid the rise of humid air currents. ”

“ If the center of the plate is devoted to one, obviously no more can be accommodated on it, but by placing one at each end, or one on each quarter of the plate, both economy of plates and convenience of printing are secured. The end may be readily accomplished by matting the plate as a negative is matted in printing. ”

“ The apparatus is of simple construction. It consists of a glass sphere silvered inside and placed before the lens of a camera, the axis of the instrument being placed parallel to the polar axis of the earth. The whole arrangement will be readily understood by an inspection of Fig. 1. The light from the sun is reflected from the globe, and some of it, passing through the lens, forms an image on a piece of prepared paper within the camera. ”

“ The elements of cyanogen, combined with sulphur, form a salt radical, sulphocyanogen, C2NS2, which is expressed by the symbol Csy. The sulphocyanide of potassium, KCsy, is prepared by fusing ferrocyanide of potassium, deprived of its water of crystallization, intimately mixed with half its weight of sulphur and 17 parts of carbonate of potassa. The molten mass, after having cooled, is exhausted with water, the solution evaporated to dryness, and extracted with alcohol, from which the crystals of the salt are separated by evaporation. ”

“ It is clear that a closed soda vessel has produced as much steam when the process is over as it has absorbed, and the quantity of coal required for the evaporation of water in concentrating the soda lye can therefore be directly compared with that required in an ordinary engine for the production of an equal quantity of steam. ”

“ The ground glass can conveniently be placed in another printing frame, and both placed up against each other. I then bring my camera into play, and so adjust the draw and distance from the negative, till I get the picture within the disk on my ground glass. I find the best way is to gum a transparency mask on the inside of the ground glass; this permits of the picture being more easily brought within the required register. This done, focus sharply, cap the lens, and then proceed to make the exposure. ”

“ A mixture of sand with a solution of caustic potash or soda is introduced into an iron boiler, under 5 or 6 atmospheres of pressure, and heated for a few hours. The iron boiler contains an agitator, which is occasionally operated during the melting. ”