We strive to deliver the best value to our customers and ensure complete satisfaction for all our textbook rentals.
You can return your online books for any reason within our refund period – no questions asked.
Every order is available for express shipping, and return shipping is always free.
You'll be happy with the quality of your books (or we'll ship you another one on our dime).
You can extend your rental up to 14 days – at the same cheap daily rental rate.
If you decide to keep the book it will never cost more than the purchase price.
As always, you have access to over 5 million titles. Plus, you can choose from 5 rental periods, so you only pay for what you’ll use. And if you ever run into trouble, our top-notch U.S. based Customer Service team is ready to help by email, chat or phone.
This historic book may have numerous typos, missing text, images, or index. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. 1902. Not illustrated. Excerpt: ... CHAPTER X. SHADOWS IN PERSPECTIVE. 187. -- Shadow is the obstruction of light. If any object is lighted from a single source, the rays of light...
This historic book may have numerous typos, missing text, images, or index. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. 1902. Not illustrated. Excerpt: ... CHAPTER X. SHADOWS IN PERSPECTIVE. 187. -- Shadow is the obstruction of light. If any object is lighted from a single source, the rays of light which fall upon it will be interrupted and a portion of space extending indefinitely behind the object will be deprived of light. This darkened space is called the invisible shadow of the object and will take the form of a cone or cylinder, the elements of which are the rays of light tangent to the object. 188. --The intersection of this invisible shadow with any plane is called the visible shadow of the object upon the plane. When the term shadow alone is used it usually means the visible shadow. In Fig. 81, 0 represents an object in space lighted by solar rays coming in the direction indicated by the arrow. The sun being at so great a distance, no appreciable error will be made if its rays are assumed to be parallel. Thus the invisible shadow of the object will take the form of a cylinder (C). The intersection of this cylinder with any plane (P) will be seen as the visible shadow (as) of the object upon the plane. 189. --If the object is reduced in size until it becomes a single point, its invisible shadow will become the single ray of light which has passed through the point. Thus the shadow of any point upon a plane is where the ray of light through the point pierces the plane. 190. --The invisible shadow of a straight line will be a plane made up of all the rays of light which pass through the line. Thus the shadow of a straight line upon a plane, being the intersection of two planes, will be a straight line. In Fig. 82, a'b' represents the shadow of the line ab upon the plane P. The shadow of any point (d) in the line, will be where the ray of light through the point crosses the shadow of the line. 191. --...
Since launching the first textbook rental site in 2006, BookRenter has never wavered from our mission to make education more affordable for all students. Every day, we focus on delivering students the best prices, the most flexible options, and the best service on earth. On March 13, 2012 BookRenter.com, Inc. formally changed its name to Rafter, Inc. We are still the same company and the same people, only our corporate name has changed.