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"38 pany owning numerous water termi- nals that a separate tugboat fire alarm system is installed on its properties with indicator and gong in the float office, where tugs are always on duty, and a tug can be brought into fire service in a few minutes. It is also the practice to assign a tugboat to the larger terminals on Sundays and holidays for fire service only. In one instance where a large wat- er-front terminal is provided with an effective private high-pressure fire line, in addition to a fleet of tugboats equipped with fire apparatus, the latter is considered fully equal in efficiency to the former. No recognition has been given to tugboat protection by underwriters. What has been done has been solely for self-protection, and it is possible, if a reasonable allowance in rate were made to owners of tugs or owners of water-front properties operating a tow- ing service, it might serve to encour- age the more general introduction of these valuable adjuncts in fire ex- tinguishment. It may be stated that the equipment described above is intended to make each tugboat about equal in efficiency to a steam fire engine. Nothing less has been considered adequate. In obtaining data for this paper the conditions in Boston, New York, Philadelphia, Baltimore, Norfolk, Buf- falo and Chicago were looked into. Boston, with its extensive and valuable waterfront, is dependent upon one city fireboat, and has no tugboats equipped with effective fire apparatus. New York and Norfolk are particu-- larly well provided with tug protec- tion, and Philadelphia and Baltimore moderately so: Practically no at- tempt has been made by tug owners in the other cities mentioned to take advantage of the possibilities of this type of fire protection. CONTRACT FOR DOCK. The San Francisco Bridge Co., of San Francisco, Cal., has been award- ed contract for building the trans- port dock at Fort Mason, in San Francisco, at a cost of over $1,000,- 000. The next lowest bidder was the American Construction Co.; of San Francisco. The proposal con- templates the construction of wharves proper, seawall, dredging and _ sheds. The successful bidder agrees to do the entire work for $1,248,000. The sum of $1,500,000 is available for im- provements at Fort Mason, of which about $250,000 will be devoted to the construction of warehouses, for which proposals will be asked later. THE MarRINE nevicw THE USE OF LIME IN THE MOD- ERN MARINE HIGH PRES- SURE BOILER. The recent great developments which have taken place in the use of H. P. steam afloat, and the consequent increase in im- portance of the generator--requiring in its manufacture high tensile steel and the best design and workmanship--call for a more scientific and careful treatment of the modern marine boiler than is usually _ given. The increase of pressure has greatly augmented the powers of the deleterious agents carried in by the feed water or produced in the boiler during working. Acids, such as oleic, also free air and the gaseous carbon dioxide and oxygen, are more readily generated or liberated under modern high-pressure conditions, and are increasingly more destructive than they were in the boilers in use ten or fifteen years ago. Taking into con- sideration the increased cost of the mod- ern boiler, in which the design, material and workmanship must be the best obtain- able, especially in a boiler of the water- tube type, all the knowledge of the marine engineer, as well as any suitable appli- ances of modern science and invention, should be requisitioned in the difficult task of preserving and keeping in efficient working order the H. P. boilers entrusted to his care. The use of an alkali as a preservative and preventative of deterioration in ma- rine boilers has always been recognized, but only in recent years has the use of! such progressed from the occasional and "guess-work" stage to that of a regular daily routine having a definite position in the care of all modern marine boiler bat- teries, where H. P. steam has made oil -and air enemies to be dreaded. Two alkalies stand out pre-eminently as 'Doiler medicines" afloat--in fact, they are the only two which can be used--lime (€a.0) and soda (Na, COs): Soda is now seldom.used for boiler work, except in very minute quantities, as it causes priming, and injury to all joints not made of.red lead--and even these are not immune if a soda solution is long in contact with them. Soda also forms a soapy-like substance with any oil in the boiler, and as this mix- ture very often sticks more firmly to the shell than the original grease, the preven- tion, in this case, is worse than the dis- ease. Nevertheless, soda is useful in a boiler which is being let out, previously to being cleaned, if it be mixed with lime and fed in cautiously, as will be described later on. Lime is now recognized as the most efficient and trustworthy agent in pre- venting the inroads of the harmful lime salts found in sea water and some fresh shore waters, the acids liberated from the various oils that find their way into the -- boiler, and the free gases carried in py the feed water or evolved in the boiler, The old method of using lime and soda by putting a solution in the feed tank has little to recommend it save its cheapness and ease. In fact it is a decidedly harmful prac- tice. In the condenser, soda especially only tends to clean out the oil and dirt, and these, as often as not, are conveyed to the one unfortunate boiler that is requiring at that moment--and getting, it is hoped, the most feed. Soda used in a condenser also frees lumps of oil and grease, which cause the air pump valves to stick and so injure the vacuum. Lime behaves better in the condenser as it finds its way to the feed tank with- out disturbing the deposits of grease. In any case, lime or soda put directly into the condenser or feed tank--whilst useful as a cleaning agent for the feed tank or condenser--generally finds its way into the boiler that is feeding at the time, in far too strong a solution and tends to make that boiler prime, besides discolor- ing its gage glasses. The use of lime in marine boilers must be considered under two heads: First, as a preservative of the surfaces of a boiler with which in a solution it is in contact when standing full, partially full or working. : Secondly, as the neutralizer of the in- jurious acids and gases which may find their way into the boiler through the feed or may be generated in the boiler where working. (1) As a preservative. When a boiler is pumped up from empty to full, lime is usually put in, in sufficient quantities to, at least, saturate the filling water. This is usually done by placing a quantity of milk of lime in the boiler and then pumping up to about 20 to 50 lbs. pressure to expel all air. This method is not to be recommended, as the circulation in a cold boiler is practically nil, and consequently when the boiler is partially full the mixing of the water and lime decreases, the inrushing water being the only stirring agent; thus intimate mixing of the water and the lime can hardly take place, and complete saturation of the water cannot be relied on as a cer- tainty. This more especially applies to the top of the boiler or upper drum, where saturation is most necessary, as all air and gases accumulate there. The bet- ter method is to have the lime regularly fed into the pumping-up water, as a much more intimate mixture of the lime and water takes place in the feed pipe and pump, and the whole mass of the water contained in the boiler is properly satur- ated.