FRANCE. ENGLAND. PRINCIPAL VOLUME. GERMANY. It is measured from the ceiling, which is usually formed by a deck. When the ceiling is curved the depth is taken from the point A, at the height where the curve stops (fig. 16). When the boilers are placed longitudinally, the length of the space left for handling the fires can not exceed the length of the grates plus 1 foot. When the boilers are placed transversely on each side of the vessel, the stoking space being in the middle, the width of the space should not exceed 11 feet. In either case the remaining space of the boiler room should not exceed what is necessary for the accommodation of the boilers. The engine and the boilers should be separated from each other only by the distance necessary for the proper operation of the former. Finally, the rear bulkhead of the engine room should not be more than 4 feet from the rear cylinder or its valve chest. In Germany there are no such restrictions. It is merely prescribed that only the space necessary for the operation of the engine and the boilers will be measured.' 1 Dimensions of engine and boiler rooms: Instructions to the ship survey, art. 16, sec. 3, provide that if firing is done longitudinally the length of space for handling can not exceed the length of the grates plus 30 centimeters. When firing is done transversely, the width of the stoking places should not exceed 3.5 meters. Technical directions, Art. VII, limits the engine room and boiler rooms to what is exclusively occupied and necessary for effective operation. The rear bulkhead of the engine room should not be over 4 feet from the rear cylinder or its valve chest unless the bureau of registry permits a greater space. FRANCE. ENGLAND. GERMANY. Certain auxiliary machinery, which forms no part of the motive machinery, is often situated in the engine room. The same is true of the machine shop. In France the volume of the machine shop is considered as engine-room space, and is added to the latter even when it is situated in a separate place. Auxiliary machines-dynamos, distilling apparatus, refrigerating machinery-are not theoretically regarded as part of the engine volume; but, in fact, when there is no real separation they are often included in the engine volume. In England the shop is in no case considered as part of the volume of the propelling machinery. Auxiliary machines are considered as part of the engines when there is no real separation. VOLUME OF VENTILATING SPACES.1 In Germany shop and auxiliary machinery are included in the engine volume when there is no real separation. An open bulkhead does not constitute real separation. The part of the ventilators under the upper deck is always considered part of the engine space. The part situated above is wholly, or partially, added thereto only when the owner demands it; the surplus, if any, is exempted. The addition, in whole, or in part, of the ventilators to the engine space is, in France and in England, subject to special rules. In France, the width must not exceed half of the greatest interior width of the vessel, The excess is not measured. In England, the ventilators must be necessary for the operation of the machinery, and must protect the machinery openings against the sea, and be reasonable in size. By reasonable in size is meant that their width must not exceed half of the greatest interior width of the vessel and that their length must not extend beyond the forward and rear bulkheads of the engine room. Lacking these conditions the space would be simply exempted. VOLUME OF THE SHAFT TUNNEL.2 In Germany, the rule requires that this space be reasonable in extent. In practice no attention is paid to this restriction.1 It is everywhere and always understood that in the engine space there is included one or more tunnels. In France no provision is made therefor. The English instructions provide for the very rare case where the shaft is not in No provision is made therefor in Germany.2 The length of light and air shafts on German ships (Technical directions, Art. VI) must not exceed the length of the engine and boiler spaces. If a part of the deck-plated over reaches into the air shaft, the length of this part is deducted from the length of the shaft which lies in this deck. The width of the air shafts must not exceed one-half of the largest interior breadth of the ship. This limitation does not hold in the case of small ships requiring greater widths. ? Provisions in Germany are now the same as in England. (Technical directions, Art. V.) The appearance of a new kind of marine engine-turbines-raises the question as to whether the deductions for engine space should not be modified. Although exact information on this space is still lacking, it seems that, for equal power, the volume of turbine engines does not differ materially from that of ordinary engines. The coal consumption also seems to be about the same. Therefore, a change in making deductions for the machinery seems scarcely probable. Moreover, potent reasons tie the hands of Governments and prevent their remedying the anomalies, recognized by all and platonically condemned for a long time, that encumber the measurement rules. APPENDIX IX. COMPARATIVE ANALYSIS OF THE PROVISIONS OF THE TONNAGE CERTIFICATES ISSUED TO VESSELS IN FRANCE, ENGLAND, AND GERMANY. |