
The Earth is Your Spaceship, by Julius Schwartz, pictures by Marc Simont, McGraw-Hill/Whittlesey House, 1963
Great cover, so-so inside illustrations, lousy text with lousy science. This book is really about the Earth, not space, but just barely- it touches on gravity, rotation and orbit, compostion of the earth, atmoshphere, but it's mostly pap.
Spaceship Earth is a merry-go-round- A merry-go-round in space That turns and turns And never stops. You can say, "Stop the earth I want to get off! But it won't And where would you go if it did? Round and round And never a stop. Round and round But your head doesn't spin. Merry-go-round Earth Takes a whole day- Twenty-four hours- For just one turn!
This book feels really 1963:
Here's some context for this cover that's meant to appeal the future space traveller in every little boy (and, not too likely, little girl):
"The first human spaceflight was Vostok 1 on April 12, 1961; Soviet cosmonaut Yuri Gagarin made one orbit around the earth...""Kennedy was eager for the United States to lead the way in the space race. Sergei Khrushchev says JFK approached his father twice about a "joint venture" in space exploration—in June 1961 and Autumn 1963. On the first occasion, Russia was far ahead of America in terms of space technology. JFK later made a speech at Rice University in September 1962, in which he said, "No nation which expects to be the leader of other nations can expect to stay behind in this race for space" and, "We choose to go to the moon in this decade and do the other things, not because they are easy, but because they are hard."[12]. On the second approach to Khrushchev, the Russian was persuaded that cost-sharing was beneficial and American space technology was forging ahead. The U.S. had launched a geo-stationary satellite and Kennedy had asked Congress to approve more than $22 billion for the Apollo Project, which had the goal of landing an American man on the moon before the end of the decade. Khrushchev agreed to a joint venture in Autumn 1963, but JFK died in November before the agreement could be formalized. In 1969, six years after Kennedy's death, the Project Apollo goal was finally realized when Neil Armstrong and Buzz Aldrin became the first men to land on the moon."
A footnote to a very interesting article titled The Ecological Colonization of Space specifies, "The first published instance of "spaceship earth" is in a children's book by Julius Schwartz, The Earth Is Your Spaceship (New York: McGraw Hill, 1963), a book that probably was inspired by (Buckminster) Fuller."
I love how crudely the figure and the transition from light to dark on the earth is drawn. And speaking of crude, see how the shadow cuts diagonally across North America on the lower left up across the North Atlantic way above Scandinavia- is that even possible?

Lentil by Robert McCloskey, published by, as it says on the title page, "The Viking Press, Inc. in May 1940." To the right, "A photo in The Columbus Citizen of McCloskey donating Lentil to the Ohioana Library in 1940. (Left to right: Mrs. J. E. Clark, Mrs. Clarence Wrum, Mr. McCloskey, Mrs. Depew Head, and Mrs. E. N. Manchester." 
" A boy named Lentil saves the day when a grumpy old man tries to ruin a small town's big celebration."
This book, by the great Robert McCloskey, author and illustrator of classics like Make Way for Ducklings and Blueberries For Sal, is fantastically illustrated. In a bit of a reversal of the trend developing in my first three book covers posts, which is that the book cover art is superior to the actual book illustrations, the drawings inside Lentil are rich, complex, and dynamic, very lively and appealing- McCloskey has a great sense of energetic line and form, and he appropriately uses just enough of the formal, academic side of drawing- persepctive, naturalistic light sources, rendering that shows lots of life drawing. Perhaps I should scan a page and show it here since I can't find images other than the cover on the web.
I'd guess that the earliest reader for this book is a very proficient second grader, but the illustrations probably cannot be fully experienced by anything less than a more cognitively-developed fourth grader. That's my guess, but there's lots of variation there depending on many factors regarding the reader.
(Incidentally, there are lots of great resources for assessing reading levels and lists of books rated by levels. Not surprisingly, much of this is targeted at home schoolers. Reading Levels of Children's Books: How Can You Tell? has a very comprehensive list of rating methods, and "Leveled Book Lists" has tons of leveled titles by grade and title; they agree with me about Lentil, rating it at 2.75, which means a grade level second grade reader three quarters of the way through that school year. Grade level reading proficiency, when demonstrated, can actually seem quite high these days if one spends a lot of time in urban school districts where many students who are second language learners are struggling with fluency. My experience as a teacher was an eye opener regarding how much of a struggle it is for students from low-literacy background to learn to read with genuine understanding and pleasure.)
But let's talk about this cover. Orange and green is a favorite color combination of mine. This scan is a little dark, but in-person the green strokes on Lentil's shirt really pop. This is a pretty simple cover that I find really relaxed and pleasing. The illustrations inside are drawn with some kind of crayon, which makes for a kind of grainy quality, while the cover seems almost painted. The line quality is solid and flowing, rather than the stop-and-start quality of drawn line. The green inside Lentil's shirt feels like four quick strokes, and the black surrounding him are a bunch of relaxed flat strokes pulling up from the sharp diagonal line over which his arms reach.
The curled shape in front of Lentil is pretty obviously the corner of a page furling back towards the reader; in terms of knowledge about the world, you can take the image literally- see it, got it, done. But visually, if you just let go of that knowledge, and let seeing take it's own path (do you know what I'm saying here- that seeing can have it's own knowledge and logic which can be completely detached from knowledge attached to language, letting seeing something become an experience of openness and possiblity and flexibilty and iterative process rather than an experience with a single finite answer), but there are two things that can plausibly deny this reading.
First, the top left corner and the fold at the right of this "page" don't extend out to the edges of the cover- the page is inset from the edges, meaning that it isn't even a complete illusionary depiction of a page. The logic isn't complete, so I can see this foldover as some other kind of shape. This is the image aspect of the cover that as the reader I can choose to go with or not.
Second, this is a cover, with a fabric background, and it's hardcover, so my seeing of these details denies that I am seeing a page. This is the object aspect of the book. My prior knowledge of what a book is informs what I know about how a book works, but it is actually my seeing that confirms this is a cover.
These may seem like small points, but it is these small points that are part of the looking experience. This is part of how I look at a painting.
Now, I know this is the curled edge of a page, but I don't have to see it that way. Two other ways I keep seeing this shape under Lentil's arms are as one side of a folded paper airplane, and also as the cover of a bed or sleeping bag folded over, which means Lentil would be laying it bed playing the harmonica. That's not McCloskey's intention, but I enjoy the possibility that I can read this image in at least three ways.
Another version of the cover (right), however, confirms more certainly what McCloskey had in mind, I think, and this version completely discards the ambiguity which I enjoy so much. This version is red, black, and white rather than orange and green, and shows off McCloskey's drawing style. I prefer my orange and green version.
Three other final things I think are worth pointing out.
The diagonal line under Lentil's arms separates two qualities: on top, there is a great variety of line- the choppiness of the black strokes' edges, the tight green in the shirt, the angualarity of the hands, the folds in the shirt. And below it's all smooth edged lines and shapes, right into the lettering. It doesn't hit you over the head, but it's a nice contrast.
The shadow under the fold is really nice- see where it's nice and fat on the right and follow it over to the left as it approaches the corner of the page and really becomes narrow- it's that little bit of thinness of the shadow that stands out and makes the page hover- that little moment is really nice, and when you broaden your vision and take in the cover as a whole that narrow little slice, postioned very near the middle of compostion, does its job without you really knowing how much power it exerts.
Finally, there's a strong triangle form present here: [1] beginning at the top left corner, trace your eyes down the straight line of the fold under Lentil's arms diagonally to the right where the shadow ends; [2] turn direction left and follow the tops of the title lettering in a straight line all the way over the spine of the book; [3] run your eyes right up the spine back to the fine point where the left and top of the depicted page join. That triangle is a central area of energy in the compositon; once you trace it it's really strong. The slight curving line of the folded over page bisects this triangle in half from apex to base. The line has a lot of presence, dividing the triangle into empty space on the left side, and the form of the curled page on the right. Inside both halves of this triangle are the projected musical notes out of Lentil's harmonica, floating over half the page and the empty space. This is the most abstract space of the image- those notes denote sound, something happening in air that we can't see, and yet visually here they are, making the most spatial, atmospheric space in the entire image. Perhap's this is why this is the area in which some kid couldn't resist drawing some stars- that's the place where something less pictorial but more energetic is happening.
One last thing: this book, like many of the others I'm showing here, is an artifact of mid-twentieth century America showing an absolute ideal white middle-America equal to your best Frank Capra effort. There is a tendency for books like this to be discarded from many school and public libraries in order to make room for a selection of books with greater ethnic, racial, and cultural diversity. Making libraries more diverse is a good thing, but it's unfortunate that a wonderfully illustrated book like McCloskey's may be set aside simply because of the era it depicted.