It's also a great example of either optimism or poor planning at the start of a major project: the three volumes are N-Z, C-M, A-B. The first volume does however have very in depth sections on accounting and anatomy (not as different as you'd expect). They did lose steam by the end, all they have to say about women is "the female of man".
It has been completely digitised (mostly for research purposes, since it is often used to determine the state of knowledge about a certain topic at the time) and is available for free online (http://www.zedler-lexikon.de). Browsing it can be very interesting and often quite amusing.
The entry for California (nowadays „Kalifornien“ in German, but „California“ in the encyclopaedia) is actually pretty long, somewhat hilarious and somewhat sad. On the issue of whether California is an island it teaches the controversy and presents both viewpoints, though clearly seems to prefer the view that California is an island.
I will try to translate the entry quite literally (paragraph breaks are inserted for better readability):
“California, also called Noua Albion [sic, should probably be Nova Albion?], an island in northern America, situated in the South Sea, reaches to New Mexico or New Granada, and is separated from them by a sea arm; however, many believe it to only be a peninsula that is connected to the mainland towards the north. In length it measures 600 or 700 French miles from north to south, from the capes Cabo blanc, Cabo S. Sebastian and Cabo Mendocino to the Cabo de S. Lucar.
The inhabitants are upstanding people, the men walk naked, the women, however, are covered to the knees in skins or feathers from the birds. The people are very skilled in hunting and fishing, as they have a special way of catching the fish.
The land is arid, barren and cold [huh?], even though it is situated where it should rather be hot or at least temperate. There are frequently grasshoppers. Pearls are found eastward on the coasts of California, just as on the coasts of New Mexico and New Granada, as first discovered by Cortesio [Hernán Cortés, I assume] in the year 1535.”
There is also an entry in a supplement volume that expands on the pearl fishing:
“California, island, [reference to previous volume]. Because the coasts there are famous for pearl fishing, the Europeans strongly wished to be there, and also, from time to time, attempted to remain there. In the beginning of the year 1703 a fortress was already built there [I wonder which fortress that is and whether it still exists in some form], so that it can serve to protect the Spaniards in an emergency. It stands in the quarter [not sure about this one, both in the German original and the translation] St Dionysii, on land that the Indians [„Indianer” in the original] call Coneho [Conejo?]. It was given the name of our dear Lady of Loretto.”
The modern town itself left a modest but pleasant impression. The nearby beaches, however, are positively epic!
'u' and 'v' were allographs for the same letter in medieval Latin (and English, etc.) -- though they became separate in around the 16th Century in English. Maybe transliteration of Latin into German kept "u" where we would use "v" longer?(Nova Albion is basically "New Britain" in Latin)
Another fun fact: Drake's circumnavigation was only the second one on record, after the Magellan expedition. Nobody had done it in the intervening 55 years.
“It is estimated that a hypothetical 1 m rise in relative sea level projected for the Gulf Coast region between Alabama and Houston over the next 50-100 years would permanently flood a third of the region’s roads as well as putting more than 70% of the region’s ports at risk,” the IPCC said.
Florida in particular also has a little issue you may have heard of with sinkholes. The geology is generally limestone, and this can be undercut by water and other effects. There's also the matter of saltwater intrusion on freshwater supplies and flora, as well as other secondary effects of seawater rise.
So I wouldn't be too sanguine.
By 2070, 56 million people in Kolkata, Mumbai, Dhaka, Guangzhou and Ho Chi Minh City will be exposed to flooding. 10 million people will be exposed in Miami, New York, New Orleans and Virginia Beach. 
The Gulf of California is narrow. In a ship, you want as much room as possible between you and unknown shores. To prove California is not an island, you would need to explore the Gulf a long way (700 miles) to reach its northern limit.
On the safer west side, you don't know ahead of time where to expect the top of the island. If you travel 1500 miles north, you might just assume the top is still further north.
Even on the west side, no settlement north of the Gulf was established until 1769 -- just seven years before Baja was determined to be a peninsula.
Most of Baja in those latitudes is desert. It's hard to make a living there, so there's not much incentive to explore.
> Spanish authorities and local residents were well aware where the actual northern terminus of the Gulf of California lay, but by extending the coastline north past Cape Mendocino and eventually even into Puget Sound, Sir Francis Drake's claim of Nova Albion for England (1579) could be invalidated by the priority of Cortes' claim (1533)
Also any voyage to west cost of the Americas at the time had to sail all the way around South America.