Machine for Sawing Rails. To the Editor of the Scientific American : I notice in a recent number of the Railway Register an article on the rail mill at Greenbush. N. Y. We have had one at Grand Island since 1879, also run by an eighty horse power engine at the rate of 3,000 revolutions per minute. The saw is forty in. in diameter, five-sixteenths inch thick, made of Bessemer steel, with a smooth edge. Two oIl-half inch pipes keep a constant current of water on it, notwithstanding which the raft' for one-eighth inch in front of the edge is made red hot by friction. The saw was made for iron rails, which it cuts in irom twenty to forty-five seconds. It has been tried on -steel rails, though it did not work. It is believed by the present general foreman, B.-G. Howard, that the reason is that iihe feed is too fast, and he intends to demonstrate tiy a series of experiments whettier- ornot steel rails can be cut by it. A Constant Reader. Grand Island,. June 10, 1886. How to Clean a Farm Hone. One of the most important things to be observed in the management of farm horses is their cleaning, and yet it may be safely stated that nothing is more neglected by the majority of farmers. The horse should never be cleaned or harnessed while it is eating breakfast. Let horses eat their food in peace, for many, from sanguine temperament or greed, bolt their oats when handled during the time of feeding. Harness can be quickly enough put oh after the feed is eaten, and time should then be taken to comb the mane and tail and use a wisp of straw on the body and legs. When the horses come in at dinner time, they should at once be unharnessed. The feed is then to be given, and before the harness is again put on, the horse should be thoroughly rubbed down with a wisp of straw or hay. If the horses are very warm on coming in, they should be rubbed down immediately after the removal of the harness. The c1M,ning or grooming, which should be done at ! night, «0)i*ists first in currying the horse with the currycomb to free him of the dirt adhering to the hair, and which, being now dry, is easily removed. A wisp-ing of straw removes the roughest of the dirt loosened by the currycomb. The leg8J-Ought to be;thorougb.ly wieped, not on ly to make them clean, but to dry up any moisture thai may have been left in the evening; and at this time the feet should be picked clean by the foot picker—i. e., an iron instrument made for the purpose—of any dirt adhering between the shoe and the foot. The brush is then to be used to remove the remaining and finer portions of dust from* the hair, which is cleared from the brush by a few rasps along the currycomb. This wisping and. brushing, if done with some force and dexterity, with a combing of the tail and mane, should render the horse pretty clean, but there are more ways of grooming a horse than one, as may be witnessed by the careless and skimming way in which many hired hands do it. The skin of the farm horse should at all times be clean if not sleek, and a slap of the hand upon the horse will show if there is loose dust in the hair. The currycomb should not be used below the knees, as it is apt to cause injury. For cleaning the legs and feet, nothing is better than the water brush; and when fitting a horse for the show-yard, it may also be used on the body with water, or even a little kerosene, but the latter is not required for common cleanliness, but merely to impart a temporary gloss. How many farmers can say that their horses are cleaned as thoroughly as we have ad vised in the above ? How much longer would horses live, work, and remain healthy if the above suggestions were put into practice ? These are questions which it will be well to consider and a!lSwer at leisure.—Farmer's Review. Treatment of Acute Rheumatism. The last number of the Russkaya Meditsina contains a communication from Dr. L. Grinevitski, of Rostoff-on-the-Don, who writes that for more than twenty years he has treated acute articular rheumatism with nitrate of potash, two drachms being given daily in raspberry sirup, and a dose administered every two hours. Together with this internal medication he prescribes an ointment for use morning and evening of the following composition: Olei hyosc., 1 oz.; ung. hydrarg. cinerei, 2 dr. ; ext.. aeon., 1 dr. He has tried all ordinary remedies, and finds that on the whole this plan of treatment is more satisfactory than any other, , being especially valuable in those cases where salicylates fail to give relief. 'Generally the disease is brought to an end in from one to two weeks, according to its severity and the time the treatment was commenced. When commenced at the onset of the attack, and before more than one joint was affected, the others were usually spared altogether.—Lancet.. ance under the control of the observer, be anchored to the wall of the observatory, so that when the dome is moved the shutter is pulled open. A ' third key will move the te' 'lope in R. A., and a fourth will-move it in declination. Lastly, we have to get the observerin-to position to observe. Instead of making him clinlb into an observing chair, which would require to be 25 ft. high, and would be very heavy to move, there is a key which causes the whole floor to move up or down, so that the observer can be brought up to within a few feet of the level of the eyepiece, and can comfortably sit on a low chair without fear of falling or accident: I am sure that an observer cannot do his best work if he is perched up at a great height above the floor, or if he has to employ any exertion in moving his seat or the instrument. The machinery which would raise the floor of the Lick Observatory would be strong enough to allow a ton and a half of observers to be carried up with it. Such a force might do some damage if the wroiigjsey weretoouched, and the.iloor went IIp while the observer had his eye at the eyepiece. I have, therefore, thought it well to provide against such an accident by hanging a weight near to the eye end of the telescope, which, when it touches the ground, would instantly cut oft' the water supply, and nothing could happen after that. The President: It makes orie feel quite envious to think of the luxuries to be provided for the astronomer of the future. The most charming part of the contrivance to me is the movement of the floor. The life of an astronomer with a key in his hand, which he only has to touch to make all these movements, Seems almost ideal—something that one might dream of, but eould not hope to realize. Mr. Common: I had the pleasure of seeing this model at the Royal Institution, and I rather hoped that it was the actual model of what they were going to have at Mount Hamilton ; but I fear that it is not so. I had a letter from Prof. Holdeu the other day, in which he says : “The glass for this lens is now finished, and we hope that during the early part of 1887 we may see the object glass finished and perhaps delivered in California. Our large dome will undoubtedly be finished during the current year, and we look forward to commencing serious work during the year 1887.” I saw in last month's Century Magazine that there is a proposal to make what they call a seven-eighths dome. That is a spherical building, or seven-eighths of a sphere, erected round the instrument. The upper hemisphere would correspond to the ordinary observatory dome with its shutters, and the lower three-eighths of the sphere would be furnished on the inside with tiers of steps, so that the observer could always get up to the eye end of the telescope. Everything which contributes to the comfort of the observer and the dispatch of business is of the utmost importance. It doubles the value of the observatory. The Deepest Boring. The deepest bore hole in the world is at Schladebach, near Kotschau Station, on the railway between Cor-betha and Leipzig, and has been undertaken by the Prussian Government in search for coal. The apparatus used is a diamond drill, down the hollow shaft of which water is forced, rising again to the surface outside the shaft of the drill and inside the tube in which the drill works. By this method cores of about 50 feet in length have been obtained. The average length bored in twenty-four hours is from 20to 33 feet, but under favorable circumstances as much as 180 feet has been bored in that time. Other deep holes are as follows : Domnitz, near Wettin................................. 3,287 feet. Probat-Jesar. Mecklenburg............................ 3,957 “ Sperenberg, near Zossen.......,....................4,173 “ Unseburg, near Stassfurt.............................. 4,242 “ .Lieth-Elmshorn, Holstein.............................. 4,390 “ Schladebach......................................... 4,515 “ The dimensions of the bore hole at Schladebach are as follows: Depths from surface. Each size bore, Feet. Diameter, Inches. ' 109 0 lOO'U ii u 605-7 416-1 9 0 661-8 56-1 73 1,906-5 1,844-7 47 8,859-8 353 3 3'6 3.543-4 1,288-6 8'8 4,069-9 5865 1-97 4,514-6 447 1-88 The various strata passed through are as follows : Soil and sand, about................................... 16 feet. Clay.................................................. 66 “ Sandstone (Bunter)................................. 459 “ Anhydrite........................................... 59 “ Brine spring............................................... Magnesian limestone (Zechstein) ..................... 144 “ Gypsum............................................ 36 “ Anhydrite.........,.................................... 295 “ Marl-slate (Kupferslfeifer)........................... 3" Sandstone (RothUegeniles)............................ 3,435 “ The bore hole, which in January, 1885, had reached a depth of 4,560 feet, was commenced in June, 1880, but left after a year's work, recommenced at the end of 1882, and is still progressing. The cost up to January, 1885, was , about $25,000.