TRANSACTIONS OF SECTION D. 639 



3. On PJiotogrnphy as an aid in Anatomical, Histological, and Emhryo- 

 logical Worh. By Professor Frasek, M.B. 



All morphologists will agree that the labour involved in illustratin<^ their 

 work properly is very great, and that any aid that would lessen this would be 

 gladly welcomed by all, especially when that aid can illustrate in a manner with- 

 which they cannot hope to compete, however skilful their pencils may be. 



In my own experience I soon found that the Camera Lucida was totally inade- 

 quate to illustrate in a reasonable time all the work which lay on my hands ; while 

 in adult anatomical work one's own hand, or even that of the skilled artist, could 

 never reproduce with the same finish and accuracy what I am now able to accom- 

 plish with but little trouble. 



In adopting the photographic method, then, I had two ends in view: the first 

 was to reproduce the entire structure of the several divisions of the body, life- 

 size ; while the object of the second was to produce etdargements of my serial 

 histological and embryological sections for purposes of reconstruction. 



For the attainment of the first end I had to employ a very large apparatus, 

 arranged to work vertically, with a rapid rectilinear lens of long focus, so as to give 

 me proper working distance to reproduce natural size, while by the correct use of 

 diaphragms (down even to pinhole ones) I was able to travel, dissection after dis- 

 section, tlirough the particular division of the body at which I was working, with- 

 out ever shifting the apparatus or the preparation; while by numerous combinations, 

 all taken direct from nature, as I went along I practically made that particular 

 division transparent. 



For the attainment of the second end I had to use an enlarging apparatus with a 

 rapid rectilinear lens of short focus and the oxyhydrogen light. In addition I had 

 special carriers made, holding twelve slides of the Leipsic or eighteen of the English 

 form at one time, so tliat I could make twelve or eighteen exposiu'es without 

 further trouble than simply pushing the carrier along the breadth of a slide and 

 changing the sensitive paper, each exposure ; using the Eastman Bromide paper 

 and full aperture of the lens lasting only four seconds. 



In this manner, then, I could run through the serial sections of a small adult 

 rodent's brain, or serial sections of embryos, in a few minutes, enlarging up at one 

 operation all the sections under a cover-glass measuring 40 by 30 mm., these 

 being often one hundred in number. 



The ease and celerity with which this can be done, and the beauty of the 

 enlargements, have to be seen to be appreciated ; whilst the every-day aid that the 

 method can yield, both in teaching and original work, will- soon lead to its more 

 general adoption. 



4. Our Local Industries in their Social and Pathological Aspects. 

 By Thomas Oliver, M.A., M.B., M.B.C.P. 



Dr. Oliver, in introducing the subject, drew attention to the frequent occurrence 

 of diseases of the cardio-vascular and nervous systems in the district — a frequency 

 explained, to a great extent, by the habits and occupations of the people. The 

 question of lead-poisoning was then discussed, as also the social life of the mdustrial 

 clas.ses. 



In the three northern counties of Northumberland, Durham, and Cumberland, 

 it is estimated that 116,690 people are employed about coal mines. To the heated 

 atmosphere of the coal mine — an atmosphere often laden with dust — and to the 

 strain thrown upon the internal organs caused by the cramped position in which 

 miners are obliged to work, were attributed some of the diseases from which coal 

 miners sufier. Half a century ago a form of phtlmis, known as anthracosis, in which 

 the lung became saturated with carbon pigment, was more or less the scourge of 

 some of tl\e mining districts. Thanks to the improved ventilation of mines, this 

 lung afTection is seldom met witli now. Beyond the frequency with which miners 

 sufier from the eflects of injuries received at work, and the fact that scrofulous 

 disease of bone and joints is of common occurrence amongst coal miners. Dr. Oliver 



