CHAP. I.] THE EQUIPMENT OF THE SHIP. 29 
was found to be 2 feet 9 inches. The microscopes are secured 
to the table by brass hold-fasts like those in common use on 
carpenters’ benches. The hold-fast, when brought to bear upon 
the back of the footpiece, holds the instrument rigidly firm. 
Two holes are bored in the table for the hold-fast, one for hold- 
ing the microscope in position when in use, and the other for 
securing it when set aside. 
The centre of the table is divided by low fixed battens into 
oblong compartments for micro-re-agents, Canada-balsam, glye- 
erine jelly, and the paraphernalia used in examining objects 
with the microscope and mounting microscopic preparations, 
ink-stands, and drawing materials. Two large moderator lamps 
swing below the cupolas; movable branches for candles are 
screwed to the bulkheads; and for examining minute surface 
animals at night, when they are frequently in greatest abun- 
dance, the Bockett microscope lamp, made by Collins, is found 
most useful. 
Three of Hartnach’s small model microscopes, with objectives 
2, 4, 7, 8, and’ 10, are in constant use in the work-room; but 
one of Smith and Beck’s binoculars is found more convenient 
for observing objects such as the large foraminifera, by reflect- 
ed light. There are also several other microscopes by Ross, 
Zeiss, and other makers, available, and a number of the ordi- 
nary dissecting microscopes. 
The heat of the tropics affects unfavorably many of the sub- 
stances In common use in mounting microscopic preparations ; 
thus, glycerine jelly will scarcely set at all, but remains near- 
ly fluid, and the different varnishes and lacs remain soft and 
sticky. It is unsafe to put preparations on edge, and we find 
small pine-wood cases, supplied by Baker and Holborn, contain- 
ing each twelve horizontal trays, with accommodation for six 
dozen slides, most suitable for storing. It is almost inconceiv- 
able how difficult it is to keep instruments, particularly those 
which are necessarily made of steel, in working order on board 
I.—3 
