N'OTICE. 



Vol. 1 of the -'Proceedings" extended from March, 1861, to Feb- 

 ruary, 1863, (2 years) and contains 381 pages. On commencing Vol. 

 2 in March, 1863, the Publication Committee proposed to terminate it 

 in December, 1864, (1 year and 10 months,) estimating that it might 

 contain about 400 or 500 pages, but by March, 1864, the estimates of 

 the Committee were so far exceeded, that it was decided to close Vol. 2 

 (containing 562 pages) at that time, and to issue Vol. 3, for the last 9 

 months of 1864, estimating that it would probably contain 400 or 500 

 pages and the 2 volumes together, over 1,000 pages, but the estimates 

 of the Committee have again been exceeded, and Vol. 3, which is com- 

 pleted by the present number, contains about 700 pages, and Vols. 2 

 and 3 together contain over 1,200 pages. With the Papers already on 

 hand and those which are known to be in preparation, the Committee 

 itoir estimates that there may be about l,OiJO pages published in 1865, 

 and in order to preserve some degree of uniformity, both in the size 

 and in the price of the Volumes of the '' Proceedings," it is proposed 

 to issue 2 Volumes for the year 1865, each containing about 500 pages. 

 The price of Vols. 1, 2 and 3, in future, will be $2.00 to Members 

 and $3.00 to the Public for each Volume. ♦ 



The price of Vols. 4 and 5 will be the same, viz. : 

 To Members (Resident and Corresponding) . $2.00 for each Vol. 

 To the Public $3.00 



Subscribers in Canada and elsewhere, to which the prepayment of 

 U. S. Postage is obligatory^ will be expected to remit, in addition to 

 the above, 20 cents on each Volume, the experience of the year 1864 

 having shown that this sum will prepay the postage on about 500 pages. 



Those who wish to continue their subscriptions old the above terms 

 are requested to remit the price of Vol 4 and ohiiyatory postage to 

 the Corresponding Secretary of the Society, No. 518 South Thirteenth 

 Street, Philadelphia, prior to April 1, 1865. A failure to remit, will 

 be considered as a withdrawal of the subscription. 



For the Plates and Wood-Cuts contained in Vol. 3, the Publication 

 Committee has been indebted to the liberality of the Authors whose 

 Papers they illustrate. 



In consequence of misapprehensions still existing in regard to Ex- 

 changes,, it is deemed advisable to reproduce the following Notice, given 

 more than 18 months since. 



" In the present state of activity in the Scientific World, it is important that 

 the Student. should receive scientific periodicals as soon after their publication 

 as practicable ; arrangements have therefore been made, by which the Society 

 will receive without delay the Publications of most importance to its Members. 

 Under these circumstances the Publication Committee has discontinued the si/s- 

 tem of making Exchanges." 



