Talk:SS Monroe (1902)

Tonnage

@Palmeira: - It's Gross Register Tonnage, not Gross Tonnage, which wasn't introduced until the late 1960s. Mjroots (talk) 15:51, 13 October 2014 (UTC)

The Forty-Second Annual List of Merchant Vessels of the United States. List of Merchant Vessels of the United States, official Department of Commerce and Labor—Bureau of Navigation registry for 1910 states "Gross tonnage" and "Net tonnage". I'm not going to speculate or argue with you on the measurement methods or who used what when—the cite, the official registry of the vessel for U.S. commerce, simply notes GT & NT. Changing that introduces speculation. I suggest we not speculate on exact measurement methods and simply roll with what the official registry of the vessel during its operation states as that is all we know. As you know there are different methods of measuring tonnage in use by different registries and there is very little in that document about how the Bureau of Navigation calculated that number. It would be interesting to see a Lloyd's for the period for comparison, but I do not have one readily available. Palmeira (talk) 16:08, 13 October 2014 (UTC)

For fun and games that Forty-Second Annual List of Merchant Vessels of the United States. List of Merchant Vessels of the United States has this note as its only definition on "tonnage" that I could find before it starts giving tonnage: "The tonnage deck, in vessels having three or more decks to the hull, shall be the second deck from below; in all other cases the upper deck of the hull is to be the tonnage deck." Now just how and where measured and how calculated for a value is not clear. The only thing I am sure about is that before modern international standards and agreements ship characteristic measurements and values were pretty chaotic, often driven by a nation's commercial interest in taxing or avoiding taxes it seems. Looking at some of the multiple "precise" engineering values for older ships makes me thing of 100 blind men describing that "elephant"! Length between perpendiculars! Which? I believe, top of head, there were at least three "perpendiculars"! Palmeira (talk) 16:21, 13 October 2014 (UTC)

It was routine to state that vessels "registered x tons gross" or were "x gross tons" when the full term in fact was "gross register tonnage". Before there was such a thing as the gross tonnage of 1969, the measure of most ships was gross register tonnage, a term often shortened as "gross tonnage". But now gross tonnage is a specific measure, different to the old measure, and former shorthand uses of "gross tonnage" do not anticipate something which did not yet exist. Wikipedia's casual use of, and link to, gross tonnage for older vessels is beyond speculative; it is incorrect, as it reads a meaning into the term which it did not have.

Even gross register tonnage had variant meanings (as shown the example of SS Leviathan), and, as you note, there are numerous ways to measure length. But the grt of, say, 1900, is not the same as the gt of today. Kablammo (talk) 18:29, 13 October 2014 (UTC)

Yes, and that is the concern. I have no idea whether the Bureau of Navigation in 1910 was using "Gross tonnage" as shorthand for GRT of their day or if their measurement resulted in the same GRT value which may have been seen in a Lloyd's Register of the same date. So, taking a value the Bureau of Navigation calls GT and assuming it is GRT, plugging it into that GRT template, could just cause problems. Unfortunately, as you note, those folks knew what they were doing, but too often did not see any reason to state just what they were doing in the documents we tend to see today. When we were last going round on these things I ran into the speed issue with SS United States which may well be someone outside Wikipedia doing a "conversion" that got reconverted to something quite unlikely. The other thing I found was that actual comparison of technical specs, done by engineers of the day, shows considerable variation in values for one ship for what we might think of as one measurement. At least they didn't state "length: 153" with us to wonder if 153 was inches, cubits, feet, meters or astronomical units! Personally, I see the infobox as a quick reference for a ship's vitals, but wonder if it does not drive an apparent simplicity and assurance that is just not there, particularly when we get into fractions of units. Palmeira (talk) 23:09, 13 October 2014 (UTC)

Example. One ship, Momus (1906), built Philadelphia, O/N 283681. U.S. Bureau of Navigation in 1910: Gross tonnage=6,878 Net tonnage=4,326. Same ship in 1933, and yes, modifications may have changed something, Lloyd's 1930—31 has 6,413 and 3,893. The 6,878 and 6,413 seem a bit close (465) for some modification and may well be due to differing measurement methods or slightly different "tonnage" type. In any case, how does one "discuss" this in an infobox? I think the only real answer is to link a value there to a specific authority and time and probably use several if available. Nobody is served by editing with "My 6,878 GRT" trumps "your 6,413 GRT" edits. Palmeira (talk) 00:15, 14 October 2014 (UTC)

Just in case that small difference was in U.S./U.K. I checked the conversions for a variety of "tons" and 6,878 converted still does not match with straight conversions being 6,141 ton (UK) and 6,239.6 ton (metric). So, baring some modification, methodology or similar difference is a distinct possibility. Palmeira (talk) 01:17, 14 October 2014 (UTC)

Gross register tonnage is tonnage, not mass. It does not measure imperial or metric tons. GRT measures volume of enclosed spaces; one gross register ton is 100 cubic feet on both sides of the Channel, and both sides of the Atlantic. There was a difference in the enclosed spaces measured by the US and those by Lloyd's, hence the difference in the case of Leviathan v. Majestic. GRT did not change but the GRT of specific vessels could and did change; the Normandie enclosed more space to leapfrog Queen Mary. The tonnage of other vessels could increase or decline as the result of modifications, but the unit of measuring tonnage did not change. Kablammo (talk) 01:35, 14 October 2014 (UTC)

Right, slipped my mind while speculating on reasons for those differences above. Yes, space is the reason for those volumetric measurements calculating tonnage and, though the volume of a "ton" did not vary, the measurement methods did vary. Palmeira (talk) 03:39, 14 October 2014 (UTC)

Are we now in agreement that it's GRT and NRT? Mjroots (talk) 07:13, 14 October 2014 (UTC)

Not at all. It is pure assumption to conclude the Bureau of Navigation's 1910 "Gross tonnage" is today's or yesterday's GRT and plug it into a tonnage slot with a template for GRT. I think you've missed the point. My "brain fart" about weight above in no way applies to the fact we do not know what parameters BoN used to come up with what it is calling "Gross tonnage" beyond the fact it appears in an official "register," it is some sort of volumetric value the registering authority is calling "Gross tonnage" and that it is most likely that it was using the one gross register ton equals 100 cubic feet measured using some sort of formula.

The core of my objection is that putting those old values into a "template" within a designated pigeonhole in an infobox implies, certainly for casual readers, that there is a singular value of known origin that is correct. That is just plain false in the case of tonnage because there were different means of obtaining a value, even different included and excluded spaces within a ship. Putting that old BoN "Gross tonnage" into your modern GRT template in the infobox slot without qualification gets us into "My 6,878 GRT"/"your 6,413 GRT" edits. Both are valid—within their context. I am increasingly coming to view those simple infobox slots as misleading simply because they imply such certainty for values (including dimensions), some of which we have little or no clue as to how measured. In fact, I recommend new templates that provide for a simple value|term|authority|date format for those before such standards; in the Monroe case as an example 4,704|gross|U.S. Bureau of Navigation|1910 while GRT|4,704|(standard) becomes the modern template. Short of that the best approach is state the value with when and by what authority obtained in the body and use that authority's own term with cite in the infobox without guessing about their term or methods in a modern, standardized context. I agree, and please do, place a footnote there explaining that the "gross" in BoN's usage is not today's Gross ton. Palmeira (talk) 14:09, 14 October 2014 (UTC)