Evidently the means of determining, even approximately, the safety of a water are at present extremely crude and unsatisfactory. It has been assumed in the above discussion that the methods of analysis employed were absolutely correct and gave absolutely correct results. When, however, we consider that the errors to which all human beings are liable, attaches to chemical manipulations as well as to any thing else, and that the "margin of error" is always an element in chemical work, and also that our process for obtaining results may contain unsuspected sources of error, the unsatisfactory nature of deductions drawn from an examination are increased. Our present methods are the best we can do, but fall very far short of what is to be desired, and what it is to be hoped we may some day attain. Respectfully submitted, ELWYN WALLER, PH. D. [No. 45.] State Board of Health of New York. REPORT ON THE METHODS AND APPARATUS FOR TESTING INFLAMMABLE OILS.* ARTHUR H. ELLIOTT, Ph. B.; F. C. S., School of Mines, Columbia College. I. INTRODUCTION. Any argument in favor of the State taking upon itself the duty of regulating the quality of kerosene oil appears very superfluous to those acquainted with the nature of the oil now sold, and the damages to life and property due to the unregulated sale of this illuminating material throughout the State. In New York city it is the province of the "Bureau of Combustibles" to test the oils sold. In the year 1880 the fire commissioners' report shows that there were 103 fires from kerosene oil lamps in a total of 1783 fires from all causes; fifty-four of these fires from kerosene are designated explosions, and from these "explosions" there was a loss by fire of $14,165. These fires occurred in spite of the vigilance of the Bureau of Combustibles in testing the kerosene oil sold in New York city. Of over nine thousand samples collected forty-three were found below the standard test of 100° Fahrenheit in Tagliabue's closed apparatus. But the loss in a city like New York, with its finely-equipped and ever-ready fire department, is no measure of the damage done in other cities and towns throughout the State, where the oil is never tested, and where the largest amount is consumed, since gas-light is not obtainable or costs much more than in New York city. The fires caused by kerosene oil lamps are rated third in point of number, and the reason there is comparatively so little damage done in a city like New York is more to the credit of the fire department than to the quality of the oil sold to poor and often ignorant people who are compelled to use it as the cheapest source of illumination. The danger from kerosene oil lies in the fact (often pointed out before) that it is a product of crude petroleum, which consists of a variety of inflammable liquids which the oil refiner should separate from one another in the most careful manner. *These investigations have been made in accordance with instructions of the State Board of Health to its Sanitary Committee, in terms as follows: "Resolved, That the Sanitary Committee be authorized to spend a sum, not exceeding one hundred and fifty dollars, in prosecuting the investigations preparatory to testing petroleum, in establishing a standard for such test in this State." E. HI. Secretary of the Board. These various liquids contained in crude petroleum are more or less volatile, and it so happens that the most volatile give the most brilliant light when burnt. It is also a fact that the vapors of the more volatile portions of crude petroleum mix very readily with air and produce mixtures that explode violently when ignited. The crude petroleum cannot be burned in a lamp without refining because of these easily ignitable vapors and also because of its odor. It then becomes the duty of the oil refiner to distill the crude oil in order to separate the more volatile liquids from those less volatile and select those best suited to burn in an ordinary kerosene lamp. From what has been said above it is obviously to the interest of the oil refiner to leave in the oil called kerosene as much of the more volatile materials as is consistent with his idea of safety, since these add materially to the brilliancy of the light. It must be further noted that it is the kerosene oil that is the most valuable to the oil refiner, since it brings a better price than the more volatile liquids, and the more of these latter he leaves in his kerosene the greater his profits. It has been left to the oil refiner to decide as to the amount of these more volatile liquids he shall leave in his products, in face of the fact that it is to his interest to leave in as much of them as possible. From a consideration of this circumstance alone, it is obvious that much oil sold in New York and elsewhere is only just able to pass when tested. under circumstances similar to those that obtain in burning in an ordinary kerosene lamp. And it cannot be doubted that in places under no supervision by inspectors, there is much oil that is dangerous to life and property. Of the 103 fires in New York city last year (1880) from kerosene oil lamps I have noted that fifty-four were caused by "explosions"; the other forty-nine were caused by the breaking of kerosene oil lamps. If the oil in these lamps had been of the proper quality these fires would not have happened, for it is only low-test oils that take fire at a low temperature. Kerosene oil with a high flashing point will have a high burning point; i. e.: Oil that will not give off inflammable vapors at a comparatively high temperature will not take fire itself until it is raised to a still higher temperature. For example, an oil that can be raised to 140 degrees Fahrenheit before it will give off an inflammable vapor can be burnt in a lamp; that lamp broken, and only the ignited wick will still burn. But under the same circumstances an oil which gives off inflammable vapors at 100 degrees Fahrenheit will not only burn at the ignited wick, but flames will run over the whole surface of the oil and envelop every thing that it comes in contact with. If we now remember that in summer our houses often have a temperature of ninety degrees Fahrenheit, and that the best oils sold in New York city will give off inflammable vapors at but a few degrees above 100, we need not be surprised at kerosene oil explosions, and fires caused by using inferior grades of oil with low flashing points. The loss of property from these causes is bad enough, but the loss of life, and more often, what is much worse, permanent injury resulting from burning with the low-grade oils, makes this matter preeminently a proper one for State regulation. It is not the better informed and intelligent citizen that runs these risks to life and property, because he uses gas or a safe kerosene oil. It is the poor and hard-working people, not so well informed, and whose few dollars have to be made to go the farthest in purchasing the necessities of life that suffer most. These people buy inferior oils because they cost a trifle less than safe ones; the management of the lamps usually falls to the lot of the women and children of the household who least appreciate the danger of handling these low-grade oils. These oils often emit enough vapor in a warm room to burn around the base of the burner in small bluish jets, and a woman or child, under such circumstances, gets frightened, lets the lamp fall, becomes enveloped in flames, and if fortunate, may escape with life and scars to be carried to the grave. This is no fancy picture, even the newspapers contain accounts of these horrors every few days, and they are generally due to the use of lowgrade kerosene oils. Any fear in handling a kerosene lamp or danger from breaking one is entirely removed by having the flashing point of the oil so high that no inflammable vapors shall be given off from it at temperatures that may obtain in the burning of an ordinary kerosene lamp. And the number of these accidents from kerosene oil shows that the oil refiners will not raise the standard of quality in refining these oils unless some pressure is brought to bear upon them by the State. To determine at what temperature a sample of kerosene oil will emit an inflammable vapor, quite a number of pieces of apparatus have been devised. The points that need attention in these apparatus are, gradual heating of the oil, an accurate register of the temperature, and a sharp and uniform means of igniting the vapor when it forms. Of the various apparatus used for this purpose I have examined the following: I. Tagliabue's Open Tester. II. Arnaboldi's Open Tester. III. Saybolt's Open Tester (Electric). IV. Tagliabue's Small-closed Tester. V. Tagliabue's Large-closed Tester. VI. Wisconsin State Tester (Loosely closed). |