ALQUIST GEARING FOR SHIP PROPULSION. 185 
It seems to me Mr, Emmet knows as much about this subject as any one, and I know 
the Parsons people are building geared drives with a guarantee of 8.5 pounds of water per 
horse-power. If we have turbines capable of making the same water rate, driving the ship 
through gearing with 98 per cent efficiency, why should we adopt the electric drive which 
gives 95 per cent efficiency when we get the same water rate out of the original turbine? 
It seems to me very peculiar that a Society such as the Society of Naval Architects and 
Marine Engineers is not represented as a Society on our Naval Board. I spoke to Secretary 
Daniels and asked him why the Society of Naval Architects and Marine Engineers was not 
represented on the Board. He said he thought it was. 
Having made plans for these battle cruisers, I have every reason to believe we can 
secure a geared drive with the same economy guaranteed and of 2,000 tons less weight, 
and as the ships are constructed, we surely need this weight. Now, if there is anything 
except the fact that they have more margin in backing power, which matters very little, 
after all, and shorter length of shafting, I would like to know what other characteristic 
favors the electric drive; for surely as an engineer who has been designing the machinery 
for battleships for twenty-five years, and one who has laid out machinery for these battle 
cruisers, I would not say that I can put geared drive in the same space with more protec- 
tion and greater economy unless I was prepared to prove it. If there is anything else left 
except the backing power and the shafting, I want to be advised of the fact, because I am 
going to write the Secretary of the Navy about it. 
THE CHAIRMAN :—The Chair has been rather liberal in the allowance of time for dis- 
cussion, and I dislike to cut people short on their discussions, or on their introductions, but 
I must remind you that we have two other papers, and if the speakers who discuss the papers 
run much beyond the five-minute limit, I will have to ask them to cut short their remarks. 
Mr. Joun H. Macarrine, Member:—The geared turbine is the most vital question 
before naval architects at the present day as it is transforming the whole field of marine 
propulsion. The reciprocating engine will now retire to second place after noble service. 
The direct-connected turbine may be said to be already obsolete. The turbo-electric drive 
will be looked back on as still-born—after the present little flurry in the United States is 
past—since it is far outclassed in every respect and for all sizes of ships, even the largest, 
by the geared turbine. Consequently, any article on the marine turbine or high-speed reduc- 
tion gears is read with deep interest. 
The present brief paper is principally remarkable for its omissions. It deals almost en- 
tirely in general statements, but gives no data from which the reader can form an inde- 
pendent opinion. 
Near the bottom of page 182 we read, “Spiral gears tend to engage by point contacts at 
or near the pitch line.” Why the author added “at or near the pitch line’ I do not know, 
but the rest of the statement is well known to be correct for gears with rigid or fixed bear- 
ings. It is also true of the Alquist gear for reasons I will partly discuss. This is the au- 
thor’s opinion, for, on page 183, second paragraph, he twice uses the term “driving points” in 
connection with the Alquist gear. The statement is not true of gears in which the pinion is 
mounted in a floating frame. In an exhaustive article published in May and June, last, by 
Engineering, London, I have shown that theory points strongly to the floating frame pro- 
ducing line contact and from data which I there give in abundance this is confirmed; for a 
floating frame gear bears continuously and safely a load from two to three times as heavy as 
