6 , RELATIVE RESISTANCES OF SOME MODELS WITH BLOCK 



anything else. I notice that in Mr. Taylor's experiments only one shallow draught was used. 

 I dare say that time and pressure of work in the basin, or other circumstances, were such as 

 to prevent a series of experiments at different draughts. 



I think it might be interesting if Mr. Taylor would state something of the nature of the 

 false bottom used, and whether it was considered that additional information of an impor- 

 tant character would be derived from a series of experiments at different draughts. 



The Chairman : — Does any other member wish to contribute to the discussion ? 



Prof. Harold A. Everett, Member: — I ask Mr. Taylor if, in his judgment, the re- 

 sults would be affected if block coefficients greater than .68 were taken, perhaps .78? 



The Chairman: — If no other member wishes to discuss the paper, we will ask Mr. 

 Taylor to close the discussion. 



Naval Constructor Taylor : — I will try to reply briefly to the questions raised. I 

 should like, first, to express my appreciation of the very kind remarks made by the gentlemen 

 who discussed the paper. 



As regards Professor Sadler's statements, I was pleased to find that his results have 

 confirmed those we found, because he has done a great deal of this work — this shallow 

 water work — and we have done very little, and, as I stated in the paper, the results were 

 rather unexpected. So I am glad that we are in agreement on that point, at any rate. I 

 am very glad he was able to throw some light on the probable cause of these unexpected re- 

 sults. I did not venture to assign a cause myself, for the simple reason that I did not know 

 what it was. We have found in most of our model work before this, and it is confirmed 

 by these experiments, that, strange as it may seem, the very full midship section is advan- 

 tageous from the point of view of resistance. I am glad such an authority as Mr. Stevenson 

 Taylor agrees with that as regards results from actual practice. Many people who build ves- 

 sels are not willing to go as far in that direction as is indicated to be desirable from the 

 results of model basin experiments. 



As regards Professor Everett's question, if you examine the diagram you will see that 

 the reduction of resistance has apparently reached its limit at a block of .64. For the blocks 

 .68 there is a very slight increase, and I should anticipate that if we had carried these experi- 

 ments in this particular case to a block of .78, deriving the .78 block in the same manner, 

 there would have been a very appreciable increase, probably a material increase, over the .68. 

 The minimum probably occurs somewhere between .64 and .68. 



With reference to Mr. Linnard's question about the false bottom, it is a fact that time 

 would not admit of the experiments being made at more than one draught, in fact we were 

 barely able to finish the shallow-water experiments in time to have the paper in the hands of 

 the printer in time for publication. The false bottom used was the bottom made originally 

 for some experiments for the New York Harbor Line Board. They wished to have some 

 experiments made on the disturbance of the water caused by the passage of ships through 

 shallow water. It is two hundred feet long, and simply a plain wooden bottom, an inch 

 thick, made in sections about 5 by 8 feet, and secured to steel beams which are heavy enough 

 to hold it down. It is arranged so that we can put it in place in two days and take it out in 

 one dav. 



