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needed. By light, frequent firing, the distillation of volatile combustible is made nearly uniform and it is at all times nearly proportional to the. air supply. Fires will be cleaner, better and easier to handle.
In closing this first talk it is desirous to summarize the points brought out. This may well be done by comparing what a Good fire is with what a Bad fire is (see page 598).
A good fire is one that is:
b. Of proper thickness. Thinner in front.
c. Shoved back from dead plate.
d. Ash-pans bright all over. If the ash-pans are brilliantly
bright the fire is too thin, or there is a hole of large size in the fire, or there are many holes.
e. Top of fire bed light (white flames) all over. Such a fire
needs coal when its turn comes.
f. A good fire is one that has an even burst of flame (white")
from its entire surface; the bottom of the fire bed has a layer of fine ash that will fall into the grates when the slice bar is swept through it and this will also indicate that the fireman is putting his coal where it is needed.
g. Clean boiler front and floor-plates.
THE SECOND TALK
The word "draft"' has been much abused by scientists and experimenters, but by the practical, operating engineer it simply names a condition that exists in his heat-producing system of boilers, fire-rooms, uptakes, smoke-pipes, the outside air, ventilators and blowers (cither exhausting fans in the uptakes or pressure fans supplying air under the grates). This "condition" produces the flow of air through the grates. It may be such as to cause a lot of air to flow, as occurs when the fire-rooms are closed and the large forced draft blowers are running, or it may be cut down by closing the dampers or stopped entirely by sealing up the boiler front.
There is not a fireman but knows that when the blowers are running it is necessary to carry heavier fires than when they are stopped. As soon as the forced draft blowers are stopped, the ventilators (openings to the outside air) must be opened. Then, instead of having the blowers creating the pressure, there is a 1
U. S. NAVAL INSTITUTE, ANNAPOLIS, MD.
THE UNITED STATES COAST GUARD: ITS
By Captain F. S. Van Boskerck, U. S. Coast Guard
The following paper was prepared several months prior to the outbreak of the present war, but it has been impracticable to print it until now.
The fact has become apparent that in the past the navy and the coast guard have not gotten sufficiently close together, but it is thought that from the beneficial results attending present association, each service will have appreciated the worth of the officers of the other, to the mutual advantage of the two services and the public interests.
Since mobilization, the enlisted personnel of the coast guard has increased until it now numbers about 6000 men—2000 more than on a peace basis—and many changes have transpired as to the disposition of the entire personnel, which is now scattered among coast guard ships, naval vessels, at air stations, in Washington, and in the several naval districts, and the need for experienced officers has been urgent.
It is suggested that now is the psychological moment to make a mental survey of conditions, to take a look at them from a fair, unbiased viewpoint, and thus to realize the errors of the past, brought about as they have been by misunderstandings and a lack of knowledge of facts.
This paper has been written with the single idea of presenting to the officers of the navy and coast guard tentative suggestions for increasing the military efficiency of the latter service, which, if adopted, would be in the best interests of the navy and the coast guard, when the relations that must exist between them in time of war are considered, or that should prevail in preparation for the same. They are not one-man ideas, but result from an experience of 29 years in the late revenue cutter service (now the coast guard) and from discussion of conditions with officers of the coast guard and of the navy, many of whom are warm advocates of the ideas advanced. If this paper serves no other end than to arouse an interest and general discussion that may be productive of results, the aim of the writer will have been accomplished.
The arm of the public service which is now the coast guard was originally established in 1790. As it increased in size, there was added a life-saving branch, which, in the course of years, became disassociated with the then revenue cutter service and was created a separate organization; but officers of the revenue cutter service continued to be detailed as inspecting officers of the life-saving service and elevated it to a high state of efficiency.
On January 28, 1915, the President signed the act of Congress creating the "United States Coast Guard," which unified the then existing revenue cutter and life-saving services. By the terms of the act, the coast guard " shall constitute a part of the military forces of the United States and shall operate under the Treasury Department in time of peace and shall operate as a part of the navy, subject to the orders of the Secretary of the Navy, in time of war, or when the President shall so direct." Thus the status of the coast guard is clearly defined and its officers and men are regulars in the same sense as are those of the army, navy, or marine corps; a fact that must not be lost sight of in following the subject matter of this paper. It is necessary for a clear understanding that we inquire into both the personnel and materiel of the coast guard to consider the strong and weak points of each and then^to take immediate advantage of the former and rectify the latter without delay.
If we consider the coast guard with respect to the numerical value of its personnel, the service may not be deemed a large one, although 4000 men are practically the equivalent of the crews of four capital ships. We must differentiate, however, as between mere " numbers " and " force " and realize that in the coast guard there lies the potentialities for the latter and advantage taken of that fact. We may here regard the words of a noted military writer as aptly applying: "The stronger each unit is in peace, the more efficient will it become for war; hence, the vital importance of aiming at quality and not numbers." We seek to increase the value of the coast guard as a "force," therefore it will become our duty to inquire as to ways and means.
The total personnel of the coast guard, as at present organized, consists of approximately 259 commissioned officers, line and staff, and about 4000 warrant officers and enlisted men. There are also 13 district superintendents who were transferred from the late life-saving service, and hold relative rank with certain grades in the commissioned rank. They are not sea-going officers.
In addition to the personnel above noted, there are at the Coast Guard Academy, Fort Trumbull, New London, three classes of cadets and cadet engineers. All of the line officers of the coast guard and practically every member of the two junior grades of engineers are graduates of that institution, while the senior grades of engineers are largely composed of graduates of colleges or technical schools where marine engineering is specialized in. The three-year course at the academy is a rigorous one, and upon graduation the cadets go forth exceptionally well equipped educationally for the profession they have chosen. That there are few "bilgers" may be attributed to the fact that the entrance examination is difficult and strictly competitive. It is also intended to assure that the successful candidate has the necessary groundwork to warrant his graduation, providing he applies himself to his studies.
It can be confidently stated that the Coast Guard Academy is yearly graduating young men who are as competent all-round officers as are to be found in any branch of the regular service.
Due to the excellent results that have eventuated from assigning junior line officers to engineering duty and junior engineers to line duty, the commandant of the coast guard has advocated the amalgamation of the engineer corps with the line, a project much to be desired, providing it can be accomplished with harmony to the best interest of the service.
While ballistics is included in the course in ordnance and gunnery, and Alger is completed, it is unfortunate that the cadets are
Returning to a consideration of Sketch No. 13. In order to obtain the pressure drop through the boiler the joint was broken at the point indicated and the manometer end thrust into the uptake. The difference in the two levels was measured as so many inches. This apparatus was used to make certain that the pressure drop through the grates of all the boilers was the same; and that the resistance of the grate when there was no coal in the furnace should not be more than one-tenth of the entire drop. This was obtained by running the forced draft blowers and measuring the total boiler drop from the ash-pit to the uptake. The pressure in the uptake was greater than atmosphere, and that in the ash-pit greater than that in the uptake. The first test of the grates showed marked variations and it was necessary to take out or put in grate bars to make them all homogeneous. By making the grates the same it was then fixed that equal division of the " draft " would not be prevented by them.
It may therefore be readily seen that after steaming, as the fires get dirty, the grates become more or less clogged and the pressure drop through the grates will increase. The amount of pressure drop through the fire bed itself is of course a variable quantity, so variable that accurate measure of it is nearly impossible. It is clear, though, that as the fires become dirty its pressure drop will increase and if the total pressure through the boiler remains constant there will be less and less available above the furnace for pushing the hot gases through the boiler and immediately the capacity of the boiler decreases. This large pressure drop nowexperienced through the grates and fire bed does not mean that the rate of combustion is high, on the contrary it is most likely to mean the opposite. It is common knowledge that if it is desired to increase the rate of combustion either (1) the fires must be worked more in order to break them up and lower their resistance, which is bad practice; or (2) more boilers must be cut in, which is good practice ; or (3) the forced draft blowers must be run, which is good practice up to the point demanding more boilers, and then again at full power, which is the point where the boilers are producing all the steam the engines will take.
(In considering the cutting in or out of boilers versus the use of forced draft, the coal used to prime furnaces and cut in the boiler must be compared to the power consumption of the fans and in connection therewith the time element of operation must be