During our 5th week of lab we learned about three more stains: the acid fast stain, endospore stain, and capsule stain.
Since our unknown was gram-positive, we could forsee what the results of the acid fast staining would be, but we did the test anyways for practice.
The purpose of this staining is to distinguish between gram positive and gram negative bacteria based on the lipid content in their cell walls: acid fast results in red colored stain, and non-acid fast results in a blue stain.
If done correctly, the staining should result in gram-positive being blue, and gram negative being red.

Gram negative bacteria contain a waxy lipid, mycolic acid, in there cell wall.  This lipid makes the cells more durable.  Acid fast cell walls are so durable that the stain (carbol fuschin) must be driven into the cells with heat.  The cells are then decolorized with acid-alcohol, all other cells will decolorize with this strong solvent, but acid fast bacteria will not.  Other cells are then counterstained with methylene blue. Thus the acid fast are left stained red by the carbol fuschin. 

This is the result of acid fast staining on our unknown, which we already knew to be gram positive, so this result was appropriate.

This is the result of the acid fast stain on our environmental bacteria which we knew to be gram negative, so this result too was appropriate. 

Next the endospore stain of our unknown revealed that our bacteria did not have endospores.

Finally, we did a capsule stain of our unknown and environmental bacteria. 

The capsule stain  selectively stains external capsules surrounding bacterial cells.  First, we prepared a smear of the bacteria in nigrosin, making a negative stain.  After allowing the smear to dry we covered it with safranin, and after letting it set, washed it off with water, blotted it dry and examined our slide.

Our result was that neither the unknown nor the environmental samples had capsules.