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tribution of the load should be about 34 per cent of the total in the for- _ward third of the whole space, 31 per cent in the midship third and 35 per- cent in the after third; in all other respects the whalebacks are working under the same conditions as other ves- sels. In giving these figures in regard to loading I may say that they have not been arrived at by opinion or arbitrarily, but by calculation from rules and form- ulae that have been proved correct by investigation and actual experiment, and in submitting them to you I fully ap- preciate the fact that owing to varying circumstances at the ore docks it is hardly ever possible to meet this dis- tribution exactly, but if it is. approxi--- mately as nearly as possible the hull will then, as far as unnecessary strains are concerned, be in the best condition that can be' looked for. Sailing in Light Condition. When sailing light or without cargo another condition is met with and one entirely peculiar to lake vessels pro- pelled by steam. When good weather prevails all that is aimed for under these circumstances is to get the. pro- -peller wheel under water and if the weight of the machinery, boilers and fuel all in the after end are not suf- ficient for this, enough water is run into the after tanks until the boat may be drawing from 14 to 15 ft. aft and Tae Marine REVIEW forward, giving the draft of 7 to 7% ft. amidships, and in this condition the vessel is subjected ° to a hogging strain, having an upward pressure at each end due to their weights not being entirely supported by the water. This condition is not very severe on the ship in calm weather, but in any kind of sea strains may be ex- tremely severe and even dangerous. It may also be greatly aggravated by a wrong manipulation of the water bal- last when it is desired to sink the -bow. This ought always to be done by flooding the ballast compartments from aft to forward until the desired draft forward and aft has been ob- tained and never by floating the ends and leaving the midship compartments empty. | There are no other points I can think of to take up with you in connection with the loading of lake vessels fur- ther than to say that it is not my pur- pose in advocating a correct distribu tion of the load to suggest that our lake vessels: need any greater care taken in the handling than does any other structure built of steel or other materials, but I do wish to ask your attention to the fact that wrong treat- ment or abuse can be the cause or destruction in part or in whole of any- thing there is, and particularly to en- gineering structures of this class. (Ap- plause). nothing at all 86. 85 _ 34,83, 82 81,30 29 28 _27 2625 24 23 22 91 90 19 18 17 16 15 14.18 12.11.10, 9 8_7_.6 252 BOL BOL BOE BOE BOL BOL BUE BOE 30E BOL 304/310 310 310 310 310 310 310 310 310 310 310 310] 298 298 298 298 298 298 298 298 298 298 forward to Discussion of Mr. Logan's Addres: Mr. Coulby--Would that distribution you have given by Percentages on the -- thirds of the cargo hold--would that be effected to any marked degree by | the size of 'the ship or does it obtain on anything down below the 600 ft. boats? That is, some of our oats have more buoyancy than others, for instance, the Bessemer boats where there is a hatch forward of the pilot house--now is the buoyancy in per- centage practically the same, that is, do we get close enough on those per- centages from the forward to the after bulkhead regardless of the location of the houses? Mr. Logan--These percentages J] have given you are approximate for all classes of boats on the lakes. When we get down to the smaller boats ees cut in more. Mr. Coulby--If they take those per- centages on all these boats from the 'the after bulkhead, dis- regarding houses, etc., and make the division equally through in thirds, they have got as practical a distribution as can be made? Mr. Logan--Yes sir. Figure it from where the ore will naturally trim for- ward to where it will naturally trim aft. Mr. Coulby--Now, gentlemen, you have all heard this very able and care- fully worked cut paper by Mr. Logan. If anybody would like to ask Mr. Logan = Ber Se 298 216 we 36 35 84 33/722 3h 30 20 | 23 | (27 | "7 oy Curve of Weight 5 Tons = 1 Inc cs } oe : oe re of Bioyainey| 5 Ton ns =1 | Ieee | | | | | | | ee. hes} | 20 (25/24 2a 22 21 | 20 /19 18 17 | 16 Ka | Ls [7X __| Curve of Hull Wt. 5 Tons sf Inch ye? Oy, Curve of Loads Tons per Inch Shearing Forces Bending Moments STEAMER HENRY H. ROGERS LOADING DIAGRAM AND CURVES OF SHEARING AND BENDING MOMENTS DIAGRAM FOR IMPROPER LOADING SCALES Weight, Buoyancy and Load Curves 5 Tons =1 Inch 60 Tons=1 Inch , 9000 Ft, Tons=1 Inch Longitudinal Scale 46=5')" Curves made for 19'3'Draft MARINE REVIEW B.G.