+- Forums (https://thenauticalalmanac.com/Forum)
+-- Forum: Main Forum Area (https://thenauticalalmanac.com/Forum/forumdisplay.php?fid=1)
+--- Forum: General Topics Here (https://thenauticalalmanac.com/Forum/forumdisplay.php?fid=2)
+--- Thread: Curious old navy math techniques. (/showthread.php?tid=212)
Curious old navy math techniques. - Rumata - 02-03-2021
Greetings, gentlemen. I found a couple of interesting old books which, considering lockdowns and general inability to cross a street without damn mask, may help to develop not very useful skills. But a lot of people have used them for sure. One of them Mathematics for navigators by Delwyn Hyatt. Yes, 1944. Of course it is kind of obsolete. But please consider the fact it was taught during WWII to officers who would serve in the real situations, not in a front of a simulator. In many cases its methods are kinda "not straight forward" to say least. But some are really good. For instance, Adding and subtracting figures from left to right, they way we write them. I tried it and after several attempts found out that it is much faster than traditional ones. Also, havesine and other formulas presented in quite different, again, not easy for me to understand, wording and form. Anyway, real navy folks really used it. So, as a due respect tio their work, let's try to understand their daily routines doing it. Not easy, my opinion.
Another one, Navigation and NAutical Astronomy, by Dutton, 1943. Again, thyere are a lot of info, which probably none of us would ever use, but there are also a lot of proves and explanations, which we take for granted without even thinking where did it come from. Moder editions of Dutton don't have some of it. I consider it as of a hystorical value.
I am always fascinated by the old methods of navigation, when Energizer' Bunny wasn't even conceived yet. No batteries, cloudy skies, rolling horizon and wet and misery all around. And they did it. Years ago we were taught to use sliding rules. It gives you anything, up to 3 decimal. Recently saw it in the antique shop for $271. And only then I realized how ancient am I.
Thank you.
Respectfully,
RE: Curious old navy math techniques. - pabrides - 02-03-2021
Nice to hear about the publications, shipmate. Something I'd be very interested in investigating.
Just because their math techniques seem antiquated doesnt mean they were wrong. Just last night I was working on a small boat design. I used a slide rule to perform every calculation and had lots of fun, but there was a certain problem with which i had trouble. So instead of continuing with decimals in that problem I tried using a fraction technique (improper fractions) learned from an old naval architecture book I've been reading and the problem worked out ok. Using fractions the old fashioned way uncomplicated the math in this instance and allowed me a better look at what was going on. As a kid in school I was taught to avoid improper fractions and I have my whole life. Now I resent those educators for narrowing my mind.
My new moto: THERE IS NOTHING IMPROPER ABOUT IMPROPER FRACTIONS
That slide rule you saw in the antique store was well overpriced. Go to garage and yard sales and you can find them for a small fraction of the shop price. Sometimes you can get them for free. Of course there are rare slide rules out there for which a collector might pay a high price, but normally slide rules are cheap. Keep looking, slide rules are not rare. There are warehouses still full of them. I just bought a perfect 10 inch engineering slide rule for $14.
My question is, are the books you mentioned available as pdf downloads?
Cheers.
RE: Curious old navy math techniques. - Rumata - 02-03-2021
Thanks for the response. Yes, I know, that that price for that particular slide ruler meant it belonged to Captain James Cook or Professor E. Fermi. At least. One of the best are the ones that were manufactured in Germany, before WWII. They were kind of slightly yellowish in color because real ivory was used. Precision and qualiity- not matched. But for a regular calcs any slide ruler would work. By the way, in Chech Republic they made it with a real big magnifying glass making calculations very handy. Regrading fractions. Yes, I also had my time with educators regarding that issue. Found it later that there iis no problem in working with that kind of fractions whatsoever.
Regarding books. Math for navigators I bought on Amazon, about $ 10.00 Plus shipping and handling. Dutton 1944, and I'm not kidding, was left on the top of the garbage can. So it was a really free lunch. Maybe later, if you want, I'll try to scan TAble of Content, and let me know what section you and other gentlemen would like to get, so I'll try to scan it. Book is only 106 pages long, and kind of half-size.
MAybe pdf is available. Just don't know.
RE: Curious old navy math techniques. - pabrides - 02-03-2021
Good on you.
Dutton is a big name in marine circles. To accept one of his books left on the garbage was smart - as long as the book doesnt smell too bad...
The other book sounds familiar but I just can't remember if I read it. Reading the contents page might serve to remind me.
BTW... Sometimes you can find slide rule accuracy to 4 or more digits. Some accurate slide rules were made in 20 inch lengths, a few even longer - more accuracy comes with slide rule length, but its not convenient to carry a 20 inch slide rule in a brief case.
Thanks for your post. I like to write stories here but it's like I'm talking to myself most of the time. Years ago there were more folks here on this site. According to the number of views there are plenty of people who visit the posts, but very few actually say anything.
Are you from czechoslovakia? My family name immigrated from there 150 years ago on a sailing ship. I may be related somehow to president Benis.
RE: Curious old navy math techniques. - Rumata - 02-03-2021
Of course, I do believe that slide ruler can be customized to any size of inner pocket or a briefcase. Sir Winston' technical adviser always had one slide ruler in his pocket. Just in a case. Once they were sitting in the empty hall waiting for a meeting to start. Sir Winston asked his Science-technical advisor: Can you tell me how much whiskey did I drink in my lifetime? His technical advisor took his truthful slide ruler, made some estimations and said: Well, My Lord, it would fill this room up to the arm-chair height." Sir Winston took a look at the arm-chair then raised his eye to the celling and said: Damn, so much to do and so little time left." Yes, slide rulers are very handy. Not sure 4 decimals are needle. Most engineering calcs I did during my career required two decimals only., NAvig trig would not require more. Anyway, plotting anything less that a thickness of a pencil lead or compass needle isn't not practical and a little bit ona side of early paranoya.
Yes, I will scan n a Table of Content. Will be sometimes next week. And I think the fact other members are reading the posts is a very good sign. Unless it is a very specific navig. question/problem they just read such stuff like this one for info only. But if you ask a specific nav. question-you will get very qualified and friendly responses. My personal experience.
NO, I'm not from Czechoslovakia. Never been over there but consider its capital, Prague a heart of Europe. And this is NOT my opinion. It is well-known fact. Cultural and historical for sure. I don't want to discuss what is going on in Europe anyway, just waste of time and space, and Czech republic is not an exception. Too obvious and very sad. One of my favorite authors is from that country. And of course my relatives-4th generation Americans also arrived to these shores on a steamer. Boing flights were overbooked.
RE: Curious old navy math techniques. - pabrides - 02-03-2021
Great reply,
but I can think of a circumstance in which 4 or more slide rule places might come in handy - such as if i should lend 347,250 and need to know my exact return at 3.72%. I'd want a slide rule accurate to 6 places, maybe 8... the ship often lent money or gave credit to sailors. The captain just took it from their wages.
Old nav or sailing books often had a chapter on ship's finances and the buying of overseas supplies and cargo. I suppose they did their important 6 digit figuring longhand. Even log tables might not account for every penny.
However, you are right in engineering terms. Why provide for 4 digit accuracy when the machinery is only capable of 3.
Great story about Winston... where in the world did you ever get that info... funny, yet a poignant truism.
I'm with you... I hardly give Europe any notice... I live in the Philippines.
RE: Curious old navy math techniques. - pabrides - 02-03-2021
Here is the closest thing I could find to the Hyatt book
http://www.survivorlibrary.com/library/the_mathematics_of_navigation_1921.pdf
RE: Curious old navy math techniques. - Rumata - 02-03-2021
Thank you.
You are right., i can't imagine anyone using a caliper , even micrometer, to get more than two decimal. Yes, one may get it and what? To boast about it to a first blonde in a Singles? What about that little drum ona sextant? There is practicality in everything, at least I see it this way, in navig that preclude us of scientific exorcises Just Because. I think nobody expressed it better than great CAptain Lecky in his Wrinkles in Practical NAvigation. When he conducted some experiments ona shore-there was a very good practical reason why did he do it.
The book you found in pdf format is much better than the one I have written about. I mean by content. The book I have in my possession is oriented on students who like math like a bride likes a pimples on her face. Not they were hating it. No They just did not know it. I tried to follow some directions and i have so much sympathy for those miserables. It is detailed, kind of intuitive, but for me it was difficult. Again, just a historical one.
Am a big fan of Sir Winston. HAve quite a lot of books written by him and a little bit about him. He was The Personality in the best meaning of this word. His career took ups and downs many times. And his childhood was kind of specific. But nobody can deprive him ofm his personal courage and absolutely fantastic determination. just one fact . He flew to the US to the meeting with FDR duing the war in a military cargo plane and his personal doctor was next to him because of a real possibility of cardiac arest. In Casablanka he almost died from a bout of pnemonia and still was able to conduct important meeting. Exceptional man. Yes, made mistakes. And who didn't . Anyway, believe it or not, even in Soviet Russia when asked whom they considered the greatest person of 20 century Russians answered Churchill, not Uncle Joe. Tells a lot.
Live in States.
RE: Curious old navy math techniques. - Rumata - 02-09-2021
Greetings,
As I've wrote, I will scan a few pages of the books just mentioned above. If anyone has any interest in more scanned pages-please, let me know. Again, it is kind of of historic interest.
RE: Curious old navy math techniques. - pabrides - 02-09-2021
If you have a chapter on how to use meridional parts that would be helpful. Or perhaps you could explain instead.
Thanks
RE: Curious old navy math techniques. - Rumata - 02-12-2021
In Bowditch and Dutton meridional parts explained in a very detailed manner
RE: Curious old navy math techniques. - Rumata - 02-13-2021
These are scanned images of pages from the old math book. Please, see the attachments. Thanks./