VERSUS FLOATING BRIDGES. 35 



As regards soot — although this introduces a new topic, as the original paper and my 

 discussion refer only to smoke, I will say that I have found fully as much soot and cin- 

 ders on the decks of our Atlantic coastwise vessels as on the decks of the river steamers, and 

 I do not think that even Mr. Bernhard will venture to maintain that our seagoing vessels 

 are absolutely out of date. 



As regards my "very unfortunate comparison between the tow barge and the self-pro- 

 pelled barge" and his "I would not for a moment care to make such a comparison" — if Mr. 

 Bernhard will read his own paper he will find in the paragraph under discussion (page 

 20, par. 3) that he compared the tow barge built by the American Bridge Company with his 

 own barge, so I am only following in his footsteps. 



As regards the speed of current — I have before me a government report which gives, 

 under the heading of "Currents Mississippi River," a table of mean cross-sectional velocities 

 for each month of the year. For February, near Fort St. Phillip below New Orleans, 6.5 knots 

 is given. It also adds : — "The greatest velocity in a given section is generally about one and 

 one-third times as great as the cross-sectional velocity." 



If this be reduced to statute miles, this gives a speed of 10 miles an hour. In some 

 of the reaches of the river nearer Cairo, this current velocity is at times materially ex- 

 ceeded, particularly near cut-offs on a rising river. 



With regard to the carrying of cargo on deck — if he will refer to the paragraph on 

 this subject in his paper he will notice that he particularly emphasizes that "I departed from 

 the old ideas and placed the cargo on deck ;" and further along in the same paragraph that 

 "by placing the cargo on deck I had the advantage, etc. * * *" My point was and is 

 that all of the river steamers carry their cargo on deck and have so carried it for many 

 years. 



With regard to the changing channels I would suggest that a study of the reports of 

 the U. S. Army Engineers would be more illuminating to Mr. Bernhard as to what the 

 Mississippi has done and is doing, than a study of the reports of the Chamber of Commerce 

 of Rotterdam, on "the change of the channel in the Rhine." Also, the next time he is going 

 up the Mississippi, if he will spend a half-hour examining the conditions at Point Pleasant 

 Reach, he will see the river preparing for a cut-off, which, il not checked by the govern- 

 ment, will cut off twenty odd miles of channel and leave New Madrid nine miles inland. 



Plate 25 shows a typical stem-wheel river steamer with the slight haze at the stack, 

 which shows good firing. The plate also shows the cargo all on deck and a construction 

 which requires careful loading and unloading in order not to destroy the structure — both 

 points for which, according to his paper, Mr. Bernhard claims original credit. 



The President : — We will now pass to Paper No. 4, entitled, "Variation of Fric- 

 tional Resistance of Ships with Condition of Wetted Surface," by Naval Constructor William 

 McEntee, U. S. N., Member. In the absence of Mr. McEntee, the paper will be presented by 

 Naval Constructor Joseph H. Linnard, U. S. N., Retired. 



Naval Constructor Linnard presented the paper. 



