On Left Wave Vatican Postmarks

Today I am trying to identify the exact postmark type for a cancellation that is on a recently purchased postcard. The cancellation mark I want to identify has seven wavey lines to the left of the postmark circle, obviously a machine cancellation. So I went to the VPS website, looked under the Reference tab, and selected the Postmark Help Id menu option. I then selected machine cancels from the drop-down menu box and then pressed the select button. The computer program searched the VPS postmark database and presented me with a number screen full of machine-canceled postmark types to look at. Looking at the selection there were five postmark types that had seven wavey lines to the left of the postmark circle. (IV-4, IV-4a, IV-4b,IV-14, IV-16). IV-14 could be eliminated because the DELL was larger than the postmark on my postcard. I clicked on the IV-16 description and some reference information about that postmark type appeared. Specifically, the recorded use date of that postmark was known to be only on 12/15/1988. My postmark date was 1/5/1974. So that eliminates IV-16. With two postmark types eliminated, guess the postmark type I am looking for is one of the IV-4 types. I clicked on each of the three remaining postmark links and read the reference descriptions very carefully. Type IV-4b stated that the P-E spread was 12mm. Got out the trusty mm ruler and found my postmark to have a P-E spread of 14mm. Just for good measure I also checked the size of the DELL and found the lettering to be only about 2 mm high. Guess I am down to type IV-4 or IV-4a. After some careful study of the lettering, and re-reading the reference I finally declared my postmark to be type IV-4a. I did use another postmark tool available on the VPS website. I went to the Reference tab and selected the menu option, Postmark List. This brought a screen to view the detail of the VPS postmark database. At the top of the screen, there is a button for Type Comparison. By clicking on the drop-down menu of the Type Comparison screen, one can see multiple examples of the various types of postmarks found in the VPS postmark library. I found another example of a IV-4a postmark and compared it to mine. I did one other thing which is very important to postmark identification. I added my postmark to the VPS postmark database. When earlier Vatican stamp collectors proposed collecting postmarks as something to be studied, they (1) set up a method of describing postmarks without graphic images, and (2) proposed that the postmark information collected be shared. The computer/internet world we live in today makes it convenient to collect, share, and have graphic images of postmarks. The more postmarks we collect in the VPS postmark database, the easier it becomes to identify what is in our own collections. So, look at your own collection and share it with the rest of us! Studying postmarks is really an enjoyable part of Vatican stamp collecting.