Square
The Square teaches masons to square their actions by the square of virtue.
Compass
Reminds masons to circumscribe and keep us within bounds with all mankind.
By-Laws
The By-Laws of a Lodge state the meeting times and days for it's stated (monthly) communications (meetings) and how misconduct will be treated and other "governing" rules.
Hat of the Worshipful Master
The only member in the lodge that is allowed to wear a hat is the Master, this is to show that he is the one leading the lodge.
Jewel of the Chaplain
The Chaplain is the religious figure of the lodge, he reads the verses during ritual and leads the lodge in prayer.
The Book of Constitutions
Where the By-Laws of the lodge regulate the lodge, the Book of Constitutions are rules of the Grand Lodge and thus are the overarching rules.
Ex. Each State has a constitution (By-laws) but the United States constitution (Book of Constitutions) still rules above the individual state's constitution.
Apron of the Chaplain
The Chaplain is the religious figure of the lodge, he reads the verses during ritual and leads the lodge in prayer.
Charter
The Charter of a lodge is that lodge's document saying that a able to meet. It is given out but the Grand Lodge and will have the signatures of the leadership of the Grand Lodge during the year it was issued.
Piano
The Piano is played by the lodge's musician. Music in the lodge often accompanies down time during ritual.
Desk of the Secretary
As with any person who's job it is to write minutes, since minutes are often hand written, the Secretary's desk is where he does his work.