Brush and MacDonnell Theodolite
Samuel Brush was a Mathematical Instrument Maker, Optician, Silversmith,  Jeweller and Watchmaker.
He operated in Melbourne at 26 Collins Street,1858 - 1862and from 69 Collins Street, 1868 - 1869.

Records also show that Brush & MacDonnell operated at 99 Collins Street 1865 -1866.

​This theodolite is circa 1860s