1879.] Compound Achromatic Microscope . 175 
Why should one flying group “ drive ” in this way, while 
other scores passed regularly on to their places ? Where 
was the commander-in-chief ? There was no struggle for 
precedence, no fighting, no pressing out of line ; here was a 
voiceless, disciplined multitude, intelligently carrying out an 
elaborate plan. 
When the line had advanced, and lay within 30 feet of 
us, we rose quickly and fired our guns over them ; and when 
this myriad rose, utterly filling the air, the broad wings 
crashed against one another with the roar of a hundred 
trains. Thus closed this most wonderful spectacle. 
A specimen we obtained measured 9J feet from tip to tip 
of the wings. The mandibles were 15 inches long, and the 
pouch held 2 quarts of wheat. 
VII. COMPOUND ACHROMATIC MICROSCOPE. 
M R. JOHN BROWNING has constructed a compound 
achromatic microscope of extremely small dimen- 
sions, the aCtual size being represented in the 
accompanying woodcut. The two powers magnify respect- 
ively about 15 and 35 diameters : the highest power is 
provided with a lieberkuhn for the illumination of opaque 
