“ If the shipper desires the lower rate, he should disclose the valuation; for, in the absence of knowledge, the carrier has a right to assume that the higher of the rates based upon value applies. In no other way can it protect itself in its right to be compensated in proportion to its insurance risk. But when a shipper delivers a package for shipment and declares a value, either upon request or voluntarily, and the carrier makes a rate accordingly, the shipper is estopped, upon plain principles of justice, from recovering, in case of loss or damage, any greater amount. ”

“ An agreement to release such a carrier for part of a loss due to negligence is no more valid than one whereby there is complete exemption. Neither is such a contract any more valid because it rests upon a consideration than if it was without consideration. A declared value by the shipper for the purpose of determining the applicable rate, when the rates are based upon valuation, is not an exemption from any part of its statutory or commonlaw liability. The right of the carrier to base rates upon value has been always regarded as just and reasonable. ”

“ When the higher rate is no more than to reasonably insure the carrier against the larger responsibility a real choice of rate is offered, and the shipper has no reasonable excuse for undervaluation. If the margin between the rates is unreasonably beyond protection against the larger risk, the shipper may be induced to misrepresent the value to escape the unreasonably high rate upon the real value. This would result in permitting the shipper to obtain a rate to which he is not entitled, and in the carrier escaping from a portion of its statutory liability. ”