14 



THE AMERICAN MONTHLY 



[January, 



is important to have the sections as 

 true as possible across the length of 

 the hair, since an oblique section 

 gives an oval outline, which might be 

 misleading. To insure the hairs all 

 being straight and parallel, a little 

 wax is placed on one end of a glass 

 slip, and the hairs inserted vertically 

 in it, singly, by making holes in the 

 wax with a warm needle. A small 

 piece of diachylon plaster is then 

 placed on the other end of the slide 

 and made to adhei-e by pressure. 

 Upon the plaster a piece of wax is 

 placed, and the hairs are one by one 

 attached to the wax by their free 

 ends, being laid parallel. To hold 

 them in place they are then coated 

 with collodion by spreading a layer 

 of that material between the two 

 points whei-e the wax is placed. 

 Several coats should be applied, un- 

 til the film of collodion is about i 

 mm. thick. If the hairs relax during 

 the process they may be straightened 

 by moving the strip of diachylon 

 plaster. 



To cut the sections the strip of col- 

 lodion may be cut up into small 

 squares, each of which may be se- 

 cured in a microtome between pieces 

 of elder-pith, soft wood, or cork. 

 The author has been able to observe 

 torsion in the hair of a negro, by cut- 

 ting a sei'ies of sections. 



The hairs are mounted in glycerin 

 or balsam without removing the col- 

 lodion which holds the sections to- 

 gether. If balsam is used, oil of 

 cloves must not be applied, as it 

 would dissolve the film of collodion. 



This ingenious method seems to 

 offer an easy means of obtaining good 

 sections of hairs, and offers an oppor- 

 tunity for some microscopist to con- 

 tribute useful information concerning 

 the form and internal structure of dif- 

 ferent varieties of hair. 



In this connection it may be said 

 that good results may be obtained in 

 double-staining sections of hair fol- 

 licles, if the proper method be fol- 

 lowed. Picro-carmine and anilin 

 violet give good i^esults. The violet 



goes to the outer layer of the inner 

 root-sheath (Henle's layer), while 

 the outer root-sheath and Huxley's 

 layer take up the picro-carmine. 



Illustrations for the Jour- 

 nal. — The editor is at present en- 

 gaged in experimenting with a pro- 

 cess of copying drawings which he 

 hopes will materially reduce the cost 

 of illustrations for the Journal and 

 at the same time yield excellent re- 

 sults — better, it is believed, than are 

 furnished by the ordinary processes 

 of photo-engraving. If these experi- 

 ments pi'ove as successful as they now 

 promise to be, it will enable us to pro- 

 vide such illustrations of microscopic 

 objects as only the excessive cost of 

 engravings has prevented us from giv- 

 ing heretofore. A good illustration is 

 equal to a page of description, and if 

 we can succeed in the eflbrts now be- 

 ing made, our readers will soon ap- 

 preciate the benefits thereof. If pos- 

 sible we will have the first illustration 

 by the process referred to in our next 

 issue, when readers may judge of the 

 capabilities of the process. 



The plan we propose to follow is to 

 illustrate, so far as possible, the more 

 common forms of minute plant and 

 animal life, giving popular descrip- 

 tions of the species, which shall be, 

 at the same time, sufficiently accurate 

 and full to enable the reader to com- 

 pare the different species that may be 

 observed with the typical forms illus- 

 trated. Such a plan carried out 

 through successive nuinbers of the 

 Journal, cannot fail to be of great 

 value to all microscopists. 



Microscopic Evidence of the 

 Antiquity of Articles of Stone. 

 — In the course of the trial arising 

 out of the disgraceful quaiTel in New- 

 York, concerning the Di Cesnola col- 

 lection at the Metropolitan Museum, 

 the miscroscope has furnished evi- 

 dence of the antiquity of certain arti- 

 cles, Mr. Benjamin Braman, Presi- 

 dent of the New-York Microscopical 



