Wetting Down a commission

In the old Navy, an officer's commission was hand-written on heavy parchment. According to some sources, the newly commissioned or promoted officer held a dinner for his shipmates and friends. During the course of the evening, the new commission was rolled into a cone, the small end folded up to form a cup. This paper cup was passed around the table for all the guests to toast the new officer. Thus, the new commission was "wetted down." Considering the importance of the document, however, this interpretation may be doubtful. Commissions inmost of  the navies were signed and issued by the President and were of great legal and personal value.

According to other sources, the wetting down party was once quite a rough and tumble affair. It was the custom for the officer to wear his new uniform or stripes for the first time at the wetting down. The guests would then proceed to christen the uniform, the occupant, and the commission with whatever liquid refreshment (paid for by the victim) was available. Over the years, however, Navy life has became more calm, the price of gold braid has skyrocketed and a literal christening is not usually condoned. It might even be considered downright unsociable.

Cumshaw

Something procured outside official channels and without official payment.  Word derived from beggars of Amoy, China, who said "kam sia" meaning "grateful -thanks."  The Navy term usually relates to unauthorized work done for a ship or station usually obtained by bartering.  "The shipyard welder added the brackets in exchange for five pounds of coffee."  A "cumshaw artist" is one who is adapt at getting projects done or items for free or by bartering.

Tending the Side.

Piping as a ceremony with side boys is a custom evolving from the days when visitors were hoisted aboard by use of the boatswain's chair.  The pipe was used for the commands "hoist away" and "avast heaving."  Members of the crew of the host ship did the hoisting.  It is from the aid they rendered in tending the side that the custom originated of having a certain number of men, ("side boys,") present.  In time it became a courtesy for high ranking officers and diplomatic officials to honored by sideboys and piping ceremony.

Fire ship

A fire ship, used in the days of wooden rowed or sailing ships, was a ship filled with combustibles, deliberately set on fire and steered (or, where possible, allowed to drift) into an enemy fleet, in order to destroy ships, or to create panic and make the enemy break formation. Ships used as fire ships were usually old and worn out or purpose-built inexpensive vessels.

Warships of the age of sail were highly vulnerable to fire. Made of wood, with seams caulked with tar, ropes greased with fat, and stores of gunpowder, there was little that would not burn. Accidental fires destroyed many ships, so fire ships presented a terrifying threat.

What happens to the magnetic compass at the magnetic pole?

A magnetic compass needle tries to align itself with the magnetic field lines. However, at (and near) the magnetic poles, the fields of force are vertically converging on the region (the inclination (I) is near 90 degrees and the horizontal intensity (H) is weak). The strength and direction tend to "tilt" the compass needle up or down into the Earth. This causes the needle to "point" in the direction where the compass is tilted regardless of the compass direction, rendering the compass useless.

There are established zones around the north and south magnetic poles where compass behavior is deemed to be "erratic" and "unusable". These zones are defined where H (the horizontal intensity) is between 3000 nT - 6000 nT (erratic zone) and H is less than 3000 nT (unusable zone).

North Magnetic Pole

The Earth's magnetic field is shaped approximately like that of a bar magnet and, like a magnet, it has two magnetic poles, one in the Canadian arctic, referred to as the North Magnetic Pole, and one off the coast of Antarctica, south of Australia, referred to as the South Magnetic Pole. At the North Magnetic Pole the Earth's magnetic field is directed vertically downward relative to the Earth's surface. Consequently, magnetic dip, or inclination is 90°. In addition, the North Magnetic Pole is the eventual destination for a traveller who follows his or her compass needle from anywhere on Earth.

The North Magnetic Pole is slowly drifting across the Canadian Arctic. The Geological Survey of Canada keeps track of this motion by periodically carrying out magnetic surveys to redetermine the Pole's location. The survey indicates position for the Pole and established that it is moving approximately northwest at 40 km per year.

The observed position for 2001 and estimated positions for 2002 to 2005 are given in the table.

Year	Latitude ( °N)	Longitude ( °W)
2001	81.3	110.8
2002	81.6	111.6
2003	82.0	112.4
2004	82.3	113.4
2005	82.7	114.4

Bosun Call

A boatswain's pipe or boatswain's call (pronounced "Bosun") is a whistle that is made of a tube, called the barrel, that directs air over a grape-sized metal sphere with a hole cut in the top. The player opens and closes the hand over the hole to change the pitch.


The historical use of the boatswain's call was as a signalling device on a ship. Because of its high pitch, it could be heard over the activities of the crew and bad weather. It is now used in the traditional color , sunset and other ceremonies of several navies, sometimes combined with other auditive features: ruffles and flourishes or even a gun salute.


It is also the Official badge of the Quartermaster in the Sea Cadet Corps

Navy Shower

Fresh water economy aboard ship may dictate using as little water as possible. Hence, the navy shower; wet down, turn off the water, soap up, turn the shower on to rinse off. If a ship's fresh water making device, the evaporators (evaps) have problems, a ship may experience "water hours" in which no showers are allowed except at select times. Generally, the smaller the ship the more experience the crew has with Navy showers.

Scuttlebutt

The origin of the word "scuttlebutt," which is nautical parlance for a rumour, comes from a combination of "scuttle" what make a hole in the ship's hull and thereby causing her to sink and "butt" is a cask or hogshead used in the days of wooden ships to hold drinking water. The cask, from which the ship's crew took their drinking water. Like water fountain was the "scuttlebutt".

Even in today's Navy a drinking fountain is referred to as such. But, since the crew used to congregate around the "scuttlebutt", that is where the rumours about the ship or voyage would begin. Thus, then and now, rumours are talk from the "scuttlebutt" or just "scuttlebutt".

Also, any ship board rumor or gossip.   "Taking a long slow drink, the sailor announced to anyone who would listen, 'We're headed for Hong Kong.  I heard it from the mess cook.'"   Scuttle-butt passes through the ship rapidly, embellished and gaining in creditability as it spreads.

Tending the Side

Piping as a ceremony with side boys is a custom evolving from the days when visitors were hoisted aboard by use of the boatswain's chair.  

The pipe was used for the commands "hoist away" and "avast heaving."  Members of the crew of the host ship did the hoisting.  It is from the aid they rendered in tending the side that the custom originated of having a certain number of men, ("side boys,") present.  

In time it became a courtesy for high ranking officers and diplomatic officials to honored by sideboys and piping ceremony

Side Boys

Side boys are a part of the quarterdeck ceremonies when an important person or Officer comes on board or leaves a ship. Large ships have side boys detailed to the quarterdeck from 0800 to sunset. When the side is piped by the BMOW, from two to eight side boys, depending on the rank of the Officer, will form a passageway at the gangway. They salute on the first note of the pipe and finish together on the last note. 

In the days of sail, it was not uncommon for the Commanding Officers of ships sailing in convoy to convene aboard the flagship for conferences. It was also not uncommon for COs to invite each other to dine aboard their vessels. Unfortunately, there was no easy way to bring visitors on and off a ship while underway. And there was no dignified may for a high ranking officer to scurry up or down a rope ladder hanging down the side of a ship. 

Often the boatswain's chair, a rope and wood sling, would be used to hoist the guest onto and off the ship. The Boatswain's Mate would control the heaving by blowing the appropriate commands with a whistle known as a Boatswain's Pipe. The number of "strong backs" needed to bring the visitor aboard depended upon the size of the "load" being hoisted. Somewhere along the line, it was noted that the more senior the visitor's rank, the more Sailors were needed to "man the side." Over time, the need to hoist visitors onto and off of Navy ships went away, but the custom of mustering the Sideboys and piping distinquished visitors aboard ship remains.

Knot

The term knot, or nautical mile, is used world-wide to denote one's speed through water. Today, we measure knots with electronic devices, but 200 years ago such devices were unknown. 

Ingenious marines devised a speed measuring device both easy to use and reliable, the "log line." From this method we get the term "Knot." The log line was a length of twine marked at 47.33-foot intervals by colored knots. At one end a log chip was fastened. It was shaped like the sector of a circle and weighted at the rounded end with lead. When thrown over the stern, it would float pointing upward and would remain relatively stationary. The log line was allowed to run free over the side for 28 seconds and then hauled on board. Knots which had passed over the side were counted. In this way, the ships speed was measured.

Crow's Nest

The raven, or crow, was an essential part of the Vikings' navigation equipment. These land-lubbing birds were carried on aboard to help the ship's navigator determine where the closest land lay when weather prevented sighting the shore. In cases of poor visibility, a crow was released and the navigator plotted a course corresponding to the bird's flight path because the crow invariably headed towards land. 

The Norsemen carried the birds in a cage secured to the top of the mast. Later on, as ships grew and the lookout stood his watch in a tub located high on the main mast, the name "crow's nest" was given to this tub. While today's Navy still uses lookouts in addition to radars, etc., the crow's nest is a thing of the past.

International code of signal and their alphabetic equivalent

Each flag represents a letter or number and can spell out a word or messsage. Each alphabetic flag can also mean a common word or phrase.

letters	phonetic alphabet	meanings
A	Alfa	Diver below, OR undergoing speed trial
B	Bravo	taking or discharging explosives
C	Charlie	Affirmative/Yes
D	Delta	Keep clear; Maneuvering with difficulty
E	Echo	Altering course to starboard
F	Foxtrot	Disabled, communicate with me
G	Golf	Need a pilot
H	Hotel	I have a pilot
I	India	Altering course to port
J	Juliette	I will send you message by semaphore; On fire with dangerous cargo, keep clear
K	Kilo	You should stop your vessel instantly. Wish to communicate
L	Lima	You should stop, I have something important to communicate
M	Mike	I have a doctor on board. Stopped and makingno way through the water
N	November	Negative/No
O	Oscar	Man overboard
P	Papa	"The Blue Peter" All aboard, vessel is about to proceed. At sea: your lights are out or burning badly
Q	Quebec	My vessel is healthy and I request free practique
R	Romeo	The way is off my ship. You may feel your way past me
S	Sierra	My engines are going full speed astern
T	Tango	Do not pass ahead of me, Keep clear, engaged in pair trawling
U	Uniform	You are coming into danger
V	Victor	I require assistance (not distress)
W	Whiskey	I require medical assistance
X	X-ray	Stop what you're doing and watch for my signals
Y	Yankee	I am carrying mails; dragging my anchor
Z	Zulu	To be used to address or call shore stations. Require tug

Flags codes

signal flags	meanings
NC	I am in distress
AC	I am abandoning my vessel
AN	I need a doctor
BR	I require a helicopter
CD	I require immediate assistance
DV	I am drifting
EF	SOS/MAYDAY has been canceled
FA	Will you give me my position?
GW	Man overboard. Please take action to pick him up
JL	You are running the risk of going aground
LO	I am not in my correct position: used by a light vessel
PD	Your navigation lights are not visible
PP	Keep well clear of me
RU	Keep clear of me; I am maneuvering with difficulty
QD	I am going ahead
QQ	I require health clearance
QT	I am going astern
QU	Anchoring is prohibited
QX	I request permission to anchor
SO	You should stop your vessel instantly
UM	The Harbor is closed to traffic
UP	Permission to enter Harbor is urgently requested. I have an emergency
YU	I am going to communicate with your station by means of the International Code of Signals
ZL	Your signal has been received but not understood.

TIDAL STREAMS

The movement of the horizontal flow of the sea is called streams. These streams when related to the rise and fall of the local tide are called tidal streams. It usually flows in and out of harbour and along the coast. The tidal stream that flow into a harbour with a rising tidal is called the “ingoing tide”. The one that flow in with a falling tide is called the “outgoing tide”. When it is off-shore, they are called according to the direction in which they flow i.e. “eastgoing” or “westgoing”. Tidal streams flow fastest where the water is deeper or the channel narrower.

Causes

Tidal streams are caused in response to the tide rising forces. It’s movements are affected by current which are caused by the differences of water temperature, barometric pressure or wing and irregularities in the seabed. It does not cause any net transfer of water with its flow.