226 THOMPSON YATES LABORATORIES REPORT 
Vlth and Vllth segments where many cells showed an obvious deviation from the normal 
condition ; in these cells the nucleus was often found placed very eccentrically, and also, on which 
fact we lay more stress, the Nissl bodies were dispersed over the body of the cell in the form of 
fine powder, and often in the central mass of a cell an actual disappearance of the blue colouring 
matter was noticed, the result of a process of chromatolysis. The proportion of altered to normal 
cells was about one in four ; they were found equally on both sides and had no special distribution 
among the various cell groups (Figs. 4 and 5). 
Fig. 4 
An altered anterior cornual cell showing chromatolysis in the centre and eccentric nucleus. The base 
of the cell is pigmented (x 1000). 
Fig. 5 
Another cell showing a similar condition. 
Remarks on the above Observations. — Although lead may primarily affect the central 
nervous system there is sufficient evidence in this case to show that the change began in the 
peripheral nerves. Firstly, the clinical picture is that of a multiple neuritis, whereas when the 
disease is primarily central the type is more that of a progressive muscular atrophy. 
Secondly, the excess of change in the peripheral nerves over that observed in the anterior 
roots points in the same direction. The neuritis is probably of a parenchymatous nature, as 
indicated by the condition of the few fibres seen degenerating and by its marked limitation to the 
