This ornately decorated spray bottle is quite remarkable; the magic imbued upon this container has the effect of magnifying the ability of the contents, largely determined by the thought of the possessor.  These powers include three main augmentations:  volumizing, magical amplification, and scent strengthening.  Each effect takes time to manifest; the longer you leave liquid within the bottle and the longer the possessor focuses his or her thought toward it, the more powerful it becomes.

For a new owner, learning the trick of concentration is the main impediment to properly utilizing the bottle.  Given the nature of Glaustick’s Cofferdam’s power, it is unlikely that any user would discern how to manipulate it without expending a great deal of time on research and experimentation.  Magical detection of the spray bottle reveals a magic of near Artifact levels.

Volumizing

If the possessor concentrates on the volume of the liquid contained for some time – say perhaps an hour a night – the contents of the bottle will double, yet the volume magically contained.  Each additional day will double again; in a week’s time, the amount contained will be 128 times the normal capacity.  Each squirt will always release one tenth of the contents.  The maximum held within the bottle is 1 million times the original volume.  Since the bottle is 1.5″ wide and 3″ tall, it holds 5.3 cubic inches of liquid at first filling (86.5 milliliters), meaning it can hold at most 22,949 gallons of liquid.  That’s a swimming pool 20′ long, 40′ wide, and 4′ deep!

Magical liquid will duplicate as well, but to a limit of 16 times the original volume – sorry, no stocking up on a swimming pool’s worth of healing potion!  Instead, a better use may be to concentrate on empowering.

Amplification

The type of concentration required to amplify the magical ability of the liquid within is quite difficult, and depending on the nature of the magic, it should typically be left to mages to perform; however, some potions can be amplified more easily by a character of a class who might use them concentrates.

Should a sufficiently strong mind concentrate in this manner, the magical power of the liquid within will grow.  To double the strength of the magic, the owner must concentrate for one hour per day for a fortnight.  This can be repeated up to 4 times; with two months of diligent work, the effect of a magical potion will be amplified to 16 times its original power.

Scent Strengthening

A less often used application of the Cofferdam is to strengthen the odor of the liquid within.  Though this may seem like the least power the Cofferdam offers, its can be very effective given the right circumstances.  There are stories that this was Glaustick’s first use of the item.  He enhanced the scent of an ambrosia potion to the point of near instant addiction for all who whiff it; they could not get enough and were driven mad.  Other stories describe his experiments with the malodorous and driving the townspeople abandoning their property, retching as they fled.  The limits of this ability barely understood; those that sought to follow Glaustick’s research quickly gave up.  The prevailing theory amongst Glaustick scholars is that, at some point in his life, he must have lost his nose.