I was in the drafting section of the local art store a couple of years ago. Next to me were a couple o' college kids who had picked up one of those motor powered erasers (remember those?) and were laughing that you'd have to be pretty bad at drawing to need a eraser that plugged into an electrical outlet. I stared at them with contempt. They had obviously never drafted with ink.

Sure, I've a soft spot for a good hand-drawn map. That's still how I map in the field. And until they get that flexible screen technology working, I'm still going to plot paper maps and roll them out on the hood of the jeep and weigh them down against the wind with rocks, a coffee mug, and my rock hammer. But comparing a hand-drawn map to a CAD drawing is to ignore a whole dimension.

A map is a 2D projection of a 3D world. A CAD drawing is a 3D world. It's not really a map, it is a model. I can observe the model from any view point and a wide range of scales. I cannot stress how important that is to geology. It'd take me forever to hand-draw an isometric view of a mine. Takes a mouse click with CAD. I can print out stereo pairs of the model. I've hand-drawn stereo pairs in the past, and it ain't easy. I can select a plane, any plane, and turn it into a cross section.

Furthermore, there is the power of layers. One of my recent drawings has more than 350 layers of information. Totally impractical in a purely paper based mapping system.

Flexibility is also a huge asset. If a client needs specific maps with specific information all I have to do is turn on those layers and plot the maps out in no time at all. Or, I can plot to a PDF and just e-mail it to the client. In the old days that would have taken days, now it takes minutes. And I haven't had to make a Blueline copy in more than a decade. Sometimes, I kinda miss that smell, though.

The ability to scale easily is also wonderful. I can take an old map, scan it, put it into the CAD model and adjust for scale and projection. Do you know what a pain that is with just pen and paper? I've used scale arms and various projectors over the years and I have to tell you CAD beats all of these, no question.

Revisions are easier, too. Hence the story about the powered eraser. Ever been a day before a meeting and the boss decides to change a drawing?

Field notes now include GPS coordinates, instead of "100 feet due east of big pine tree on ridge."

Dimensions, perimeters, areas, volumes, and angles can all be measured with both accuracy and precision, down to several significant figures.

Survey data drops right into the model from a spread-sheet.

I can include hyperlinks - click on a sample symbol and go to the assay information. Click on a mine and see its production.

Air photos work so much easier in CAD than paper.

Oh, and then there is the size factor. Some maps are just to damn big to do by hand. I worked on a project years ago where our map (in order to be at a usable scale) was 4 feet wide and 16 feet long. No problem in CAD.

You want to hire me to map your property and give you a hand-drawn map as a deliverable? Okay. I'll assemble it in CAD, plot it out and trace it onto mylar with my old ink pens (if I can get them un-clogged). It's gonna cost you, though, and by the hour, too. (maybe I'll out-source it to some un-employed monks somewhere)